AUTHOR OF THIS BLOG

DR ANTHONY MELVIN CRASTO, WORLDDRUGTRACKER

Dihydrobenzofuran Neolignans

 Uncategorized  Comments Off on Dihydrobenzofuran Neolignans
May 132016
 

Figure 1 Structures of dihydrobenzofuran neolignans 2a and 2b. 

Scheme 1 (i) Ag2O, (CH3)2CO:C6H6 3:5, r.t., 20 h (2a: 36% yield; 2b: 43% yield). 

Figure 3  Main nuclear Overhauser effect (NOE) correlations observed in the nuclear Overhauser effect spectroscopy (NOESY) spectra of compounds 2a and 2b. 

Table 1 1H and 13C NMR data assignments for compound 2a (400 MHz, CDCl3) 

δCa δH (integral, multiplicityb), J/ Hz
1 132.0 (C) −
2=6 127.5 (CH) 7.27 (2H, ddd, J2,5 = J6,3 0.3, J2,7 = J6,7 0.6, J2,3 = J6,5 8.3)
3=5 115.7 (CH) 6.84 (2H, dd, J3,6 = J5,2 0.3, J3,2 = J5,6 8.3)
4 156.1 (C) −
7 87.7 (CH) 6.09 (1H, dt, J7,2 = J7,6 0.6, J7,8 7.2)
8 55.1 (CH) 4.27 (1H, dd, J8,6′ 1.4, J8,7 7.2)
9 170.9 (C) −
10 52.9 (CH3) 3.83 (3H, s)
1′ 127.8 (C) −
2′ 130.8 (CH) 7.43 (1H, ddd, J2′,7‘ 1.1, J2′,6′ 2.0, J2′,3′ 8.3)
3′ 110.3 (CH) 6.89 (1H, dd, J3′,6′ 0.4, J3′,2′8.3)
4′ 161.2 (C) −
5′ 125.1 (C) −
6′ 124.9 (CH) 7.55 (1H, dddd, J6′,3′ 0.4, J6′,7′ 0.7, J6′,8 1.4, J6′,2′2.0)
7′ 144.7 (CH) 7.66 (1H, ddd, J7′,6′ 0.7, J7′,2′ 1.1, J7′,8′ 15.9)
8′ 115.2 (CH) 6.32 (1H, d, J8′,7′ 15.9)
9′ 167.9 (C) −
10′ 51.7 (CH3) 3.81 (3H, s)

aMultiplicities assigned on the basis of distortionless enhancement by polarization transfer (DEPT) 135 experiments;

bmultiplicities and coupling constant values measured within 1H NMR and J-resolved spectra with the help from1H-1H correlation spectroscopy (COSY) results.

Table 2 2D NMR data for compound 2a (400 MHz, CDCl3) 

C H gCOSYa gHMBCb gHMQCc NOESYd
1 – – H3 =H5, H7, H8 – –
2=6 2=6 H3, H5, H7 H3 =H5, H7 H2=H6 H7, H8
3=5 3=5 H2, H6 H5 H3=H5 –
4 – – H3 =H5, H2 =H6 – –
7 7 H2=H6, H8 H6, H8 H7 H2=H6*
8 8 H7, H6′ H7, H6′ H8 H2=H6, H6′*
9 – – H7, H8, H10 – –
10 10 – − H10 –
1′ – – H3′, H8′ – –
2′ 2′ H3′, H6′, H7′ H6′, H7′ H2′ H7′, H8′*
3′ 3′ H2′, H6′ − H3′ –
4′ – – H2′, H3′, H6′, H7, H8 – –
5′ – – H8, H3′ – –
6′ 6′ H2′, H3′, H7′, H8 H2′, H7′, H8 H6′ H8′, H7′, H8*
7′ 7′ H2′, H8′, H6′ H2′, H6′, H8′ H7′ H6′*, H2′
8′ 8′ H7′ H7′ H8′ H6′*, H2′
9′ – – H7′, H8′, H10′ – –
10′ 10′ – – H10′ –

bgradient-selected heteronuclear multiple bond coherence;
cgradient-selected heteronuclear multiple quantum coherence;
dnuclear Overhauser effect spectroscopy.
*mean weak correlation.

aGradient-selected correlation spectroscopy;

Table 3 1H and 13C NMR data assignments for compound 2b (400 MHz, acetone-d6) 

δCa δH (integral, multiplicityb); J/ Hz
1 132.5 (C) –
2 111.2 (CH) 7.10 (1H, ddd, J2,5 0.3, J2,7 0.8, J2,6 2.1)
3 149.1 (C) –
4 148.5 (C) –
5 116.3 (CH) 6.84 (1H, dd, J5,2 0.3, J5,6 8.3)
6 120.7 (CH) 6.92 (1H, ddd, J6,7 0.6, J6,2 2.1, J6,5 8.3)
7 88.8 (CH) 6.04 (1H, ddd, J7,6 0.6, J7,2 0.8, J7,8 7.3)
8 57.0 (CH) 4.47 (1H, dd, J8,6′ 1.4, J8,7 7.3)
9 172.1 (C=O) –
10 53.5 (CH3) 3.81 (3H, s)
11 56.4 (CH3) 3.84 (3H, s)
1′ 129.9 (C) –
2′ 113.9 (CH) 7.33 (1H, dd, J2′,7′ 0.4, J2’6′ 2.6)
3′ 146.3 (C) –
4′ 151.5 (C) –
5′ 127.8 (C) –
6′ 119.5 (CH) 7.29 (1H, ddd, J6′,7′ 0.8, J6′,8 1.4, J6′,2′ 2.6)
7′ 145.9 (CH) 7.63 (1H, ddd, J7′,2′ 0.4, J7′,6′ 0.8, J7′,8′ 15.8)
8′ 116.8 (CH) 6.44 (1H, d, J8′,7′ 15.8)
9′ 168.2 (C) –
10′ 52.1 (CH3) 3.73 (3H, s)
11′ 56.8 (CH3) 3.92 (3H, s)

aMultiplicities assigned on the basis of distortionless enhancement by polarization transfer (DEPT) 135 experiments;
bmultiplicities and coupling constant values measured within 1H-NMR and J-resolved spectra with the help from1H-1H correlation spectroscopy (COSY) results.

Table 4 2D NMR data for compound 2b (400 MHz, acetone-d6) 

C H gCOSYa gHMBCb gHMQCc NOESYd
1 – – H2, H6, H7, H8 – –
2 2 H5, H6, H7 H5, H6, H7 H2 H7, H8, H11
3 – – H2, H5, H11 H3 –
4 – – H2, H5, H6 – –
5 5 H2, H6 H6 H5 –
6 6 H2, H5, H7 H2, H5 H6 H7, H8
7 7 H2, H6, H8 H2, H6, H8 H7 H6*, H2
8 8 H6′, H7 H2, H6′ H8 H6′*, H2, H6
9 – – H7, H8, H10 H9 –
10 10 – − H10 –
11 11 – − H11 H2
1′ – – H7′, H8′ H1′ –
2′ 2′ H6′, H7′ H6′, H7′ H2′ H7′, H8′*, H11′
3′ – – H11′ – –
4′ – – H2′, H6′, H7, H8 – –
5′ – – H7, H8′ – –
6′ 6′ H7′, H2′, H8 H2′, H7′, H8 H6′ H8′, H7′, H8*
7′ 7′ H2′, H6′, H8′ H2′, H6′, H8′ H7′ H6′, H2′,
8′ 8′ H7′ H7′ H8′ H6′, H2′
9′ – – H8′, H10′ – –
10′ 10′ – – H10′ –
11′ 11′ – – H11′ H2′

aGradient-selected correlation spectroscopy;
bgradient-selected heteronuclear multiple bond coherence;
cgradient-selected heteronuclear multiple quantum coherence;
dnuclear Overhauser effect spectroscopy.
*mean weak correlation.

1H and 13C NMR data previously reported for compound2a and 2b were obtained in CDCl3 or acetone-d6. Most of the signals in the 1H NMR spectrum were between δH 6.0 and δH 8.0, but the hydrogen signal multiplicities are ambiguous. In this work, we found that for compound2a in acetone-d6, the signals at δH 7.6-7.7 are referred to four hydrogen atoms and their overlapping precluded their correct assignment (Figure 2). Therefore, CDCl3 provided much clearer spectra for 2a, but not for 2b, due to the solvent influence on chemical shifts. For compound 2b, three hydrogen atoms resonate at δH 6.91 in the 1H HMR spectrum in CDCl3. On the other hand, the 1H NMR signals of 2b were resolved by using acetone-d6 as solvent, which allowed verification of the multiplicities, observation of the chemical shifts and measurement of the coupling constants.

Figure 2 Expansions of the 1H NMR spectrum of compounds 2a and 2b obtained in CDCl3 and acetone-d6. 

 

Journal of the Brazilian Chemical Society

On-line version ISSN 1678-4790

J. Braz. Chem. Soc. vol.27 no.1 São Paulo Jan. 2016

http://dx.doi.org/10.5935/0103-5053.20150262

ARTICLES

Detailed 1H and 13C NMR Spectral Data Assignment for Two Dihydrobenzofuran Neolignans

Talita C. T. Medeirosa  #, Herbert J. Diasa  #, Eliane O. Silvaa  , Murilo J. Fukuib  , Ana Carolina F. Soaresb  , Tapas Karc  , Vladimir C. G. Helenob  , Paulo M. Donatea  , Renato L. T. Parreirab  , Antônio E. M. Crottia  * 

aDepartamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, 14040-901 Ribeirão Preto-SP, Brazil

bNúcleo de Pesquisas em Ciências Exatas e Tecnológicas, Universidade de Franca, 14404-600 Franca-SP, Brazil

cDepartment of Chemistry and Biochemistry, Utah State University, 84322-0300 Logan-UT, United States

ABSTRACT

In this work we present a complete proton (1H) and carbon 13 (13C) nuclear magnetic resonance (NMR) spectral analysis of two synthetic dihydrofuran neolignans (±)-trans-dehydrodicoumarate dimethyl ester and (±)-trans-dehydrodiferulate dimethyl ester. Unequivocal assignments were achieved by 1H NMR, proton decoupled 13C (13C{1H}) NMR spectra, gradient-selected correlation spectroscopy (gCOSY), J-resolved, gradient-selected heteronuclear multiple quantum coherence (gHMQC), gradient-selected heteronuclear multiple bond coherence (gHMBC) and nuclear Overhauser effect spectroscopy (NOESY) experiments. All hydrogen coupling constants were measured, clarifying all the hydrogen signals multiplicities. Computational methods were also used to simulate the 1H and 13C chemical shifts and showed good agreement with the transconfiguration of the substituents at C7 and C8.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532016000100136&lng=en&nrm=iso&tlng=en

Key words: neolignans,  oxidative coupling,  J-resolved,  benzofurans

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see……….0103-5053-jbchs-27-01-0136-suppl01.pdf

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Printing with Collagen

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May 132016
 

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Printing with Collagen

Addition of collagen to hydrogels in 3D printing improves stem cell differentiation in osteogenesis

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http://www.chemistryviews.org/details/news/9268521/Printing_with_Collagen.html

 

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Collagen

Tropocollagen molecule: three left-handed procollagens (red, green, blue) join to form a right handed triple helical tropocollagen.

Collagen is the most common protein found in mammals.

Collagen /ˈkɒlədʒᵻn/ is the main structural protein in the extracellular space in the various connective tissues in animal bodies. As the main component of connective tissue, it is the most abundant protein in mammals,[1] making up from 25% to 35% of the whole-body protein content. Depending upon the degree of mineralization, collagen tissues may be rigid (bone), compliant (tendon), or have a gradient from rigid to compliant (cartilage).[2] Collagen, in the form of elongated fibrils, is mostly found in fibrous tissues such as tendons, ligaments and skin. It is also abundant incorneas, cartilage, bones, blood vessels, the gut, intervertebral discs and the dentin in teeth.[3] In muscle tissue, it serves as a major component of the endomysium. Collagen constitutes one to two percent of muscle tissue, and accounts for 6% of the weight of strong, tendinous muscles.[4] Thefibroblast is the most common cell that creates collagen.

Gelatin, which is used in food and industry, is collagen that has been irreversibly hydrolyzed.[5] Collagen also has many medical uses in treating complications of the bones and skin.

The name collagen comes from the Greek κόλλα (kólla), meaning “glue“, and suffix -γέν, -gen, denoting “producing”.[6][7] This refers to the compound’s early use in the process of boiling the skin and sinews of horses and other animals to obtain glue.

 

 

woman receiving injection to forehead
Collagen injections can be used in cosmetic procedures to improve the contours of aging skin.

Types of collagen

Collagen occurs in many places throughout the body. Over 90% of the collagen in the human body, however, is type I.[8]

So far, 28 types of collagen have been identified and described. They can be divided into several groups according to the structure they form:[2]

  • Fibrillar (Type I, II, III, V, XI)
  • Non-fibrillar
    • FACIT (Fibril Associated Collagens with Interrupted Triple Helices) (Type IX, XII, XIV, XVI, XIX)
    • Short chain (Type VIII, X)
    • Basement membrane (Type IV)
    • Multiplexin (Multiple Triple Helix domains with Interruptions) (Type XV, XVIII)
    • MACIT (Membrane Associated Collagens with Interrupted Triple Helices) (Type XIII, XVII)
    • Other (Type VI, VII)

The five most common types are:

  • Type I: skin, tendon, vascular ligature, organs, bone (main component of the organic part of bone)
  • Type II: cartilage (main collagenous component of cartilage)
  • Type III: reticulate (main component of reticular fibers), commonly found alongside type I.
  • Type IV: forms basal lamina, the epithelium-secreted layer of the basement membrane.
  • Type V: cell surfaces, hair and placenta

wrinkled mouth with cigarette
Tobacco contains chemicals that damage collagen

Medical uses

Cardiac applications

The collagenous cardiac skeleton which includes the four heart valve rings, is histologically and uniquely bound to cardiac muscle. The cardiac skeleton also includes the separating septa of the heart chambers – the interventricular septum and the atrioventricular septum. Collagen contribution to the measure of cardiac performance summarily represents a continuous torsional force opposed to the fluid mechanics of blood pressure emitted from the heart. The collagenous structure that divides the upper chambers of the heart from the lower chambers is an impermeable membrane that excludes both blood and electrical impulses through typical physiological means. With support from collagen, atrial fibrillation should never deteriorate to ventricular fibrillation. Collagen is layered in variable densities with cardiac muscle mass. The mass, distribution, age and density of collagen all contribute to the compliance required to move blood back and forth. Individual cardiac valvular leaflets are folded into shape by specialized collagen under variable pressure. Gradual calcium deposition within collagen occurs as a natural function of aging. Calcified points within collagen matrices show contrast in a moving display of blood and muscle, enabling methods of cardiac imaging technology to arrive at ratios essentially stating blood in (cardiac input) and blood out (cardiac output). Pathology of the collagen underpinning of the heart is understood within the category of connective tissue disease.

Hydrolyzed type II collagen and osteoarthritis

A published study[9] reports that ingestion of a novel low molecular weight hydrolyzed chicken sternal cartilage extract, containing a matrix of hydrolyzed type II collagen,chondroitin sulfate, and hyaluronic acid, relieves joint discomfort associated with osteoarthritis. A randomized controlled trial (RCT) enrolling 80 subjects demonstrated that it was well tolerated with no serious adverse event and led to a significant improvement in joint mobility compared to the placebo group on days 35 (p = 0.007) and 70 (p < 0.001).

 

Fast facts on collagen

Here are some key points about collagen. More detail and supporting information is in the main article.25-27

  • Protein makes up around 20% of the body’s mass, and collagen makes up around 30% of the protein in the human body.
  • There are at least 16 types of collagen, but 80-90% of the collagen in the body consists of types I, II, and III.
  • Type I collagen fibrils are stronger than steel (gram for gram).
  • Collagen is most commonly found within the body in the skin, bones and connective tissues.
  • The word “collagen” is derived from the Greek “kolla,” meaning glue.
  • Collagen gives the skin its strength and structure, and also plays a role in the replacement of dead skin cells.
  • Collagen production declines with age (as part of intrinsic aging), and is reduced by exposure to ultraviolet light and other environmental factors (extrinsic aging).
  • Collagen in medical products can be derived from human, bovine, porcine and ovine sources.
  • Collagen dressings attract new skin cells to wound sites.
  • Cosmetic products such as revitalizing lotions that claim to increase collagen levels are unlikely to do so, as collagen molecules are too large to be absorbed through the skin.
  • Collagen production can be stimulated through the use of laser therapy and the use of all-trans retinoic acid (a form ofvitamin A).
  • Controllable factors that damage the production of collagen include sunlight, smoking and high sugar consumption.

Cosmetic surgery

Collagen has been widely used in cosmetic surgery, as a healing aid for burn patients for reconstruction of bone and a wide variety of dental, orthopedic, and surgical purposes. Both human and bovine collagen is widely used as dermal fillers for treatment of wrinkles and skin aging.[10] Some points of interest are:

  1. When used cosmetically, there is a chance of allergic reactions causing prolonged redness; however, this can be virtually eliminated by simple and inconspicuous patch testing prior to cosmetic use.
  2. Most medical collagen is derived from young beef cattle (bovine) from certified BSE-free animals. Most manufacturers use donor animals from either “closed herds”, or from countries which have never had a reported case of BSE such as Australia, Brazil, and New Zealand.

Bone grafts

As the skeleton forms the structure of the body, it is vital that it maintains its strength, even after breaks and injuries. Collagen is used in bone grafting as it has a triple helical structure, making it a very strong molecule. It is ideal for use in bones, as it does not compromise the structural integrity of the skeleton. The triple helical structure of collagen prevents it from being broken down by enzymes, it enables adhesiveness of cells and it is important for the proper assembly of the extracellular matrix.[11]

Tissue regeneration

Collagen scaffolds are used in tissue regeneration, whether in sponges, thin sheets, or gels. Collagen has the correct properties for tissue regeneration such as pore structure, permeability, hydrophilicity and it is stable in vivo. Collagen scaffolds are also ideal for the deposition of cells, such as osteoblasts and fibroblasts and once inserted, growth is able to continue as normal in the tissue.[12]

Reconstructive surgical uses

Collagens are widely employed in the construction of the artificial skin substitutes used in the management of severe burns. These collagens may be derived from bovine, equine, porcine, or even human sources; and are sometimes used in combination with silicones, glycosaminoglycans, fibroblasts, growth factors and other substances.

Collagen is also sold commercially in pill form as a supplement to aid joint mobility. However, because proteins are broken down into amino acids before absorption, there is no reason for orally ingested collagen to affect connective tissue in the body, except through the effect of individual amino acid supplementation.

Collagen is also frequently used in scientific research applications for cell culture, studying cell behavior and cellular interactions with the extracellular environment.[13]

Wound care

Collagen is one of the body’s key natural resources and a component of skin tissue that can benefit all stages of the wound healing process.[14] When collagen is made available to the wound bed, closure can occur. Wound deterioration, followed sometimes by procedures such as amputation, can thus be avoided.

Collagen is a natural product, therefore it is used as a natural wound dressing and has properties that artificial wound dressings do not have. It is resistant against bacteria, which is of vital importance in a wound dressing. It helps to keep the wound sterile, because of its natural ability to fight infection. When collagen is used as a burn dressing, healthygranulation tissue is able to form very quickly over the burn, helping it to heal rapidly.[15]

Throughout the 4 phases of wound healing, collagen performs the following functions in wound healing:

  • Guiding function: Collagen fibers serve to guide fibroblasts. Fibroblasts migrate along a connective tissue matrix.
  • Chemotactic properties: The large surface area available on collagen fibers can attract fibrogenic cells which help in healing.
  • Nucleation: Collagen, in the presence of certain neutral salt molecules can act as a nucleating agent causing formation of fibrillar structures. A collagen wound dressing might serve as a guide for orienting new collagen deposition and capillary growth.
  • Hemostatic properties: Blood platelets interact with the collagen to make a hemostatic plug.

Chemistry

The collagen protein is composed of a triple helix, which generally consists of two identical chains (α1) and an additional chain that differs slightly in its chemical composition (α2).[16] The amino acid composition of collagen is atypical for proteins, particularly with respect to its high hydroxyproline content. The most common motifs in the amino acid sequence of collagen are glycine–proline-X and glycine-X-hydroxyproline, where X is any amino acid other than glycine, proline or hydroxyproline. The average amino acid composition for fish and mammal skin is given.[16]

Amino acid Abundance in mammal skin
(residues/1000)		 Abundance in fish skin
(residues/1000)
Glycine 329 339
Proline 126 108
Alanine 109 114
Hydroxyproline 95 67
Glutamic acid 74 76
Arginine 49 52
Aspartic acid 47 47
Serine 36 46
Lysine 29 26
Leucine 24 23
Valine 22 21
Threonine 19 26
Phenylalanine 13 14
Isoleucine 11 11
Hydroxylysine 6 8
Methionine 6 13
Histidine 5 7
Tyrosine 3 3
Cysteine 1 1
Tryptophan 0 0

Synthesis

First, a three-dimensional stranded structure is assembled, with the amino acids glycine and proline as its principal components. This is not yet collagen but its precursor, procollagen. Procollagen is then modified by the addition of hydroxyl groups to the amino acids proline and lysine. This step is important for later glycosylation and the formation of the triple helix structure of collagen. The hydroxylase enzymes that perform these reactions require Vitamin C as a cofactor, and a deficiency in this vitamin results in impaired collagen synthesis and the resulting disease scurvy[17] These hydroxylation reactions are catalyzed by two different enzymes: prolyl-4-hydroxylase[18] and lysyl-hydroxylase. Vitamin C also serves with them in inducing these reactions. In this service, one molecule of vitamin C is destroyed for each H replaced by OH. [19] The synthesis of collagen occurs inside and outside of the cell. The formation of collagen which results in fibrillary collagen (most common form) is discussed here. Meshwork collagen, which is often involved in the formation of filtration systems, is the other form of collagen. All types of collagens are triple helices, and the differences lie in the make-up of the alpha peptides created in step 2.

  1. Transcription of mRNA: About 34 genes are associated with collagen formation, each coding for a specific mRNA sequence, and typically have the “COL” prefix. The beginning of collagen synthesis begins with turning on genes which are associated with the formation of a particular alpha peptide (typically alpha 1, 2 or 3).
  2. Pre-pro-peptide formation: Once the final mRNA exits from the cell nucleus and enters into the cytoplasm, it links with the ribosomal subunits and the process of translation occurs. The early/first part of the new peptide is known as the signal sequence. The signal sequence on the N-terminal of the peptide is recognized by a signal recognition particle on the endoplasmic reticulum, which will be responsible for directing the pre-pro-peptide into the endoplasmic reticulum. Therefore, once the synthesis of new peptide is finished, it goes directly into the endoplasmic reticulum for post-translational processing. It is now known as pre-pro-collagen.
  3. Pre-pro-peptide to pro-collagen: Three modifications of the pre-pro-peptide occur leading to the formation of the alpha peptide:
    1. The signal peptide on the N-terminal is dissolved, and the molecule is now known as propeptide (not procollagen).
    2. Hydroxylation of lysines and prolines on propeptide by the enzymes ‘prolyl hydroxylase’ and ‘lysyl hydroxylase’ (to produce hydroxyproline and hydroxylysine) occurs to aid cross-linking of the alpha peptides. This enzymatic step requires vitamin C as a cofactor. In scurvy, the lack of hydroxylation of prolines and lysines causes a looser triple helix (which is formed by three alpha peptides).
    3. Glycosylation occurs by adding either glucose or galactose monomers onto the hydroxyl groups that were placed onto lysines, but not on prolines.
    4. Once these modifications have taken place, three of the hydroxylated and glycosylated propeptides twist into a triple helix forming procollagen. Procollagen still has unwound ends, which will be later trimmed. At this point, the procollagen is packaged into a transfer vesicle destined for the Golgi apparatus.
  4. Golgi apparatus modification: In the Golgi apparatus, the procollagen goes through one last post-translational modification before being secreted out of the cell. In this step, oligosaccharides (not monosaccharides as in step 3) are added, and then the procollagen is packaged into a secretory vesicle destined for the extracellular space.
  5. Formation of tropocollagen: Once outside the cell, membrane bound enzymes known as ‘collagen peptidases’, remove the “loose ends” of the procollagen molecule. What is left is known as tropocollagen. Defects in this step produce one of the many collagenopathies known as Ehlers-Danlos syndrome. This step is absent when synthesizing type III, a type of fibrilar collagen.
  6. Formation of the collagen fibril: ‘Lysyl oxidase’, an extracellular enzyme, produces the final step in the collagen synthesis pathway. This enzyme acts on lysines and hydroxylysines producing aldehyde groups, which will eventually undergo covalent bonding between tropocollagen molecules. This polymer of tropocollogen is known as a collagen fibril.

Action of lysyl oxidase

Amino acids

Collagen has an unusual amino acid composition and sequence:

  • Glycine is found at almost every third residue.
  • Proline makes up about 17% of collagen.
  • Collagen contains two uncommon derivative amino acids not directly inserted during translation. These amino acids are found at specific locations relative to glycine and are modified post-translationally by different enzymes, both of which require vitamin C as acofactor.

Cortisol stimulates degradation of (skin) collagen into amino acids.[20]

Collagen I formation

Most collagen forms in a similar manner, but the following process is typical for type I:

  1. Inside the cell
    1. Two types of alpha chains are formed during translation on ribosomes along the rough endoplasmic reticulum (RER): alpha-1 and alpha-2 chains. These peptide chains (known as preprocollagen) have registration peptides on each end and a signal peptide.
    2. Polypeptide chains are released into the lumen of the RER.
    3. Signal peptides are cleaved inside the RER and the chains are now known as pro-alpha chains.
    4. Hydroxylation of lysine and proline amino acids occurs inside the lumen. This process is dependent on ascorbic acid (vitamin C) as a cofactor.
    5. Glycosylation of specific hydroxylysine residues occurs.
    6. Triple alpha helical structure is formed inside the endoplasmic reticulum from two alpha-1 chains and one alpha-2 chain.
    7. Procollagen is shipped to the Golgi apparatus, where it is packaged and secreted by exocytosis.
  2. Outside the cell
    1. Registration peptides are cleaved and tropocollagen is formed by procollagen peptidase.
    2. Multiple tropocollagen molecules form collagen fibrils, via covalent cross-linking (aldol reaction) by lysyl oxidase which links hydroxylysine and lysine residues. Multiple collagen fibrils form into collagen fibers.
    3. Collagen may be attached to cell membranes via several types of protein, including fibronectin and integrin.

Synthetic pathogenesis

Vitamin C deficiency causes scurvy, a serious and painful disease in which defective collagen prevents the formation of strong connective tissue. Gums deteriorate and bleed, with loss of teeth; skin discolors, and wounds do not heal. Prior to the 18th century, this condition was notorious among long-duration military, particularly naval, expeditions during which participants were deprived of foods containing vitamin C.

An autoimmune disease such as lupus erythematosus or rheumatoid arthritis[21] may attack healthy collagen fibers.

Many bacteria and viruses secrete virulence factors, such as the enzyme collagenase, which destroys collagen or interferes with its production.

Molecular structure

A single collagen molecule, tropocollagen, is used to make up larger collagen aggregates, such as fibrils. It is approximately 300 nm long and 1.5 nm in diameter, and it is made up of three polypeptide strands (called alpha peptides, see step 2), each of which has the conformation of a left-handed helix – this should not be confused with the right-handedalpha helix. These three left-handed helices are twisted together into a right-handed triple helix or “super helix”, a cooperative quaternary structure stabilized by many hydrogen bonds. With type I collagen and possibly all fibrillar collagens, if not all collagens, each triple-helix associates into a right-handed super-super-coil referred to as the collagen microfibril. Each microfibril is interdigitated with its neighboring microfibrils to a degree that might suggest they are individually unstable, although within collagen fibrils, they are so well ordered as to be crystalline.

Three polypeptides coil to form tropocollagen. Many tropocollagens then bind together to form a fibril, and many of these then form a fibre.

A distinctive feature of collagen is the regular arrangement ofamino acids in each of the three chains of these collagen subunits. The sequence often follows the pattern Gly–Pro-X or Gly-X-Hyp, where X may be any of various other amino acid residues.[16] Proline or hydroxyproline constitute about 1/6 of the total sequence. With glycine accounting for the 1/3 of the sequence, this means approximately half of the collagen sequence is not glycine, proline or hydroxyproline, a fact often missed due to the distraction of the unusual GX1X2 character of collagen alpha-peptides. The high glycine content of collagen is important with respect to stabilization of the collagen helix as this allows the very close association of the collagen fibers within the molecule, facilitating hydrogen bonding and the formation of intermolecular cross-links.[16]This kind of regular repetition and high glycine content is found in only a few other fibrous proteins, such as silk fibroin.

Collagen is not only a structural protein. Due to its key role in the determination of cell phenotype, cell adhesion, tissue regulation and infrastructure, many sections of its non-proline-rich regions have cell or matrix association / regulation roles. The relatively high content of proline and hydroxyproline rings, with their geometrically constrained carboxyl and (secondary) amino groups, along with the rich abundance of glycine, accounts for the tendency of the individual polypeptide strands to form left-handed helices spontaneously, without any intrachain hydrogen bonding.

Because glycine is the smallest amino acid with no side chain, it plays a unique role in fibrous structural proteins. In collagen, Gly is required at every third position because the assembly of the triple helix puts this residue at the interior (axis) of the helix, where there is no space for a larger side group than glycine’s single hydrogen atom. For the same reason, the rings of the Pro and Hyp must point outward. These two amino acids help stabilize the triple helix—Hyp even more so than Pro; a lower concentration of them is required in animals such as fish, whose body temperatures are lower than most warm-blooded animals. Lower proline and hydroxyproline contents are characteristic of cold-water, but not warm-water fish; the latter tend to have similar proline and hydroxyproline contents to mammals.[16] The lower proline and hydroxproline contents of cold-water fish and other poikilotherm animals leads to their collagen having a lower thermal stability than mammalian collagen.[16] This lower thermal stability means that gelatin derived from fish collagen is not suitable for many food and industrial applications.

The tropocollagen subunits spontaneously self-assemble, with regularly staggered ends, into even larger arrays in the extracellular spaces of tissues.[22][23] Additional assembly of fibrils is guided by fibroblasts, which deposit fully formed fibrils from fibripositors.[2] In the fibrillar collagens, the molecules are staggered from each other by about 67 nm (a unit that is referred to as ‘D’ and changes depending upon the hydration state of the aggregate). Each D-period contains four plus a fraction collagen molecules, because 300 nm divided by 67 nm does not give an integer (the length of the collagen molecule divided by the stagger distance D). Therefore, in each D-period repeat of the microfibril, there is a part containing five molecules in cross-section, called the “overlap”, and a part containing only four molecules, called the “gap”.[24] The triple-helices are also arranged in a hexagonal or quasihexagonal array in cross-section, in both the gap and overlap regions.[24][25]

There is some covalent crosslinking within the triple helices, and a variable amount of covalent crosslinking between tropocollagen helices forming well organized aggregates (such as fibrils).[26] Larger fibrillar bundles are formed with the aid of several different classes of proteins (including different collagen types), glycoproteins and proteoglycans to form the different types of mature tissues from alternate combinations of the same key players.[23] Collagen’s insolubility was a barrier to the study of monomeric collagen until it was found that tropocollagen from young animals can be extracted because it is not yet fully crosslinked. However, advances in microscopy techniques (i.e. electron microscopy (EM) and atomic force microscopy (AFM)) and X-ray diffraction have enabled researchers to obtain increasingly detailed images of collagen structure in situ. These later advances are particularly important to better understanding the way in which collagen structure affects cell–cell and cell–matrix communication, and how tissues are constructed in growth and repair, and changed in development and disease.[27][28] For example, using AFM–based nanoindentation it has been shown that a single collagen fibril is a heterogeneous material along its axial direction with significantly different mechanical properties in its gap and overlap regions, correlating with its different molecular organizations in these two regions.[29]

Collagen fibrils/aggregates are arranged in different combinations and concentrations in various tissues to provide varying tissue properties. In bone, entire collagen triple helices lie in a parallel, staggered array. 40 nm gaps between the ends of the tropocollagen subunits (approximately equal to the gap region) probably serve as nucleation sites for the deposition of long, hard, fine crystals of the mineral component, which is (approximately) Ca10(OH)2(PO4)6.[30] Type I collagen gives bone its tensile strength.

Associated disorders

Collagen-related diseases most commonly arise from genetic defects or nutritional deficiencies that affect the biosynthesis, assembly, postranslational modification, secretion, or other processes involved in normal collagen production.

Genetic Defects of Collagen Genes
Type Notes Gene(s) Disorders
I This is the most abundant collagen of the human body. It is present in scar tissue, the end product when tissue heals by repair. It is found in tendons, skin, artery walls, cornea, the endomysiumsurrounding muscle fibers, fibrocartilage, and the organic part of bones and teeth. COL1A1, COL1A2 Osteogenesis imperfecta, Ehlers–Danlos syndrome, Infantile cortical hyperostosis a.k.a. Caffey’s disease
II Hyaline cartilage, makes up 50% of all cartilage protein. Vitreous humour of the eye. COL2A1 Collagenopathy, types II and XI
III This is the collagen of granulation tissue, and is produced quickly by young fibroblasts before the tougher type I collagen is synthesized. Reticular fiber. Also found in artery walls, skin, intestines and the uterus COL3A1 Ehlers–Danlos syndrome, Dupuytren’s contracture
IV Basal lamina; eye lens. Also serves as part of the filtration system in capillaries and the glomeruli ofnephron in the kidney. COL4A1, COL4A2,COL4A3, COL4A4,COL4A5, COL4A6 Alport syndrome, Goodpasture’s syndrome
V Most interstitial tissue, assoc. with type I, associated with placenta COL5A1, COL5A2,COL5A3 Ehlers–Danlos syndrome (Classical)
VI Most interstitial tissue, assoc. with type I COL6A1, COL6A2,COL6A3, COL6A5 Ulrich myopathy, Bethlem myopathy,Atopic dermatitis[31]
VII Forms anchoring fibrils in dermoepidermal junctions COL7A1 Epidermolysis bullosa dystrophica
VIII Some endothelial cells COL8A1, COL8A2 Posterior polymorphous corneal dystrophy 2
IX FACIT collagen, cartilage, assoc. with type II and XI fibrils COL9A1, COL9A2,COL9A3 EDM2 and EDM3
X Hypertrophic and mineralizing cartilage COL10A1 Schmid metaphyseal dysplasia
XI Cartilage COL11A1, COL11A2 Collagenopathy, types II and XI
XII FACIT collagen, interacts with type I containing fibrils, decorin and glycosaminoglycans COL12A1 –
XIII Transmembrane collagen, interacts with integrin a1b1, fibronectin and components of basement membranes like nidogen and perlecan. COL13A1 –
XIV FACIT collagen, also known as undulin COL14A1 –
XV – COL15A1 –
XVI – COL16A1 –
XVII Transmembrane collagen, also known as BP180, a 180 kDa protein COL17A1 Bullous pemphigoid and certain forms of junctional epidermolysis bullosa
XVIII Source of endostatin COL18A1 –
XIX FACIT collagen COL19A1 –
XX – COL20A1 –
XXI FACIT collagen COL21A1 –
XXII – COL22A1 –
XXIII MACIT collagen COL23A1 –
XXIV – COL24A1 –
XXV – COL25A1 –
XXVI – EMID2 –
XXVII – COL27A1 –
XXVIII – COL28A1 –

In addition to the above-mentioned disorders, excessive deposition of collagen occurs in scleroderma.

Diseases

One thousand mutations have been identified in twelve out of more than twenty types of collagen. These mutations can lead to various diseases at the tissue level.[32]

Osteogenesis imperfecta – Caused by a mutation in type 1 collagen, dominant autosomal disorder, results in weak bones and irregular connective tissue, some cases can be mild while others can be lethal, mild cases have lowered levels of collagen type 1 while severe cases have structural defects in collagen.[33]

Chondrodysplasias – Skeletal disorder believed to be caused by a mutation in type 2 collagen, further research is being conducted to confirm this.[34]

Ehlers-Danlos Syndrome – Six different types of this disorder, which lead to deformities in connective tissue. Some types can be lethal, leading to the rupture of arteries. Each syndrome is caused by a different mutation, for example type four of this disorder is caused by a mutation in collagen type 3.[35]

Alport syndrome – Can be passed on genetically, usually as X-linked dominant, but also as both an autosomal dominant and autosomal recessive disorder, sufferers have problems with their kidneys and eyes, loss of hearing can also develop in during the childhood or adolescent years.[36]

Osteoporosis – Not inherited genetically, brought on with age, associated with reduced levels of collagen in the skin and bones, growth hormone injections are being researched as a possible treatment to counteract any loss of collagen.[37]

Knobloch syndrome – Caused by a mutation in the COL18A1 gene that codes for the production of collagen XVIII. Patients present with protrusion of the brain tissue and degeneration of the retina, an individual who has family members suffering from the disorder are at an increased risk of developing it themselves as there is a hereditary link.[32]

Characteristics

Collagen is one of the long, fibrous structural proteins whose functions are quite different from those of globular proteins, such as enzymes. Tough bundles of collagen calledcollagen fibers are a major component of the extracellular matrix that supports most tissues and gives cells structure from the outside, but collagen is also found inside certain cells. Collagen has great tensile strength, and is the main component of fascia, cartilage, ligaments, tendons, bone and skin.[38][39] Along with elastin and soft keratin, it is responsible for skin strength and elasticity, and its degradation leads to wrinkles that accompany aging.[10] It strengthens blood vessels and plays a role in tissue development. It is present in the cornea and lens of the eye in crystalline form. It may be one of the most abundant proteins in the fossil record, given that it appears to fossilize frequently, even in bones from the Mesozoic and Paleozoic.[40]

Uses

Collagen has a wide variety of applications, from food to medical. For instance, it is used in cosmetic surgery and burn surgery. It is widely used in the form of collagen casings for sausages, which are also used in the manufacture of musical strings.

If collagen is subject to sufficient denaturation, e.g. by heating, the three tropocollagen strands separate partially or completely into globular domains, containing a different secondary structure to the normal collagen polyproline II (PPII), e.g. random coils. This process describes the formation of gelatin, which is used in many foods, including flavoredgelatin desserts. Besides food, gelatin has been used in pharmaceutical, cosmetic, and photography industries.[41] From a nutritional point of view, collagen and gelatin are a poor-quality sole source of protein since they do not contain all the essential amino acids in the proportions that the human body requires—they are not ‘complete proteins‘ (as defined by food science, not that they are partially structured). Manufacturers of collagen-based dietary supplements usually containing hydrolyzed collagen claim that their products can improve skin and fingernail quality as well as joint health. However, mainstream scientific research has not shown strong evidence to support these claims.[42]Individuals with problems in these areas are more likely to be suffering from some other underlying condition (such as normal aging, dry skin, arthritis etc.) rather than just a protein deficiency.

From the Greek for glue, kolla, the word collagen means “glue producer” and refers to the early process of boiling the skin and sinews of horses and other animals to obtain glue. Collagen adhesive was used by Egyptians about 4,000 years ago, and Native Americans used it in bows about 1,500 years ago. The oldest glue in the world, carbon-dated as more than 8,000 years old, was found to be collagen—used as a protective lining on rope baskets and embroidered fabrics, and to hold utensils together; also in crisscross decorations on human skulls.[43] Collagen normally converts to gelatin, but survived due to dry conditions. Animal glues are thermoplastic, softening again upon reheating, and so they are still used in making musical instruments such as fine violins and guitars, which may have to be reopened for repairs—an application incompatible with tough, syntheticplastic adhesives, which are permanent. Animal sinews and skins, including leather, have been used to make useful articles for millennia.

Gelatin-resorcinol–formaldehyde glue (and with formaldehyde replaced by less-toxic pentanedial and ethanedial) has been used to repair experimental incisions in rabbit lungs.[44]

History

The molecular and packing structures of collagen have eluded scientists over decades of research. The first evidence that it possesses a regular structure at the molecular level was presented in the mid-1930s.[45][46] Since that time, many prominent scholars, including Nobel laureates Crick, Pauling, Rich and Yonath, and others, including Brodsky,Berman, and Ramachandran, concentrated on the conformation of the collagen monomer. Several competing models, although correctly dealing with the conformation of each individual peptide chain, gave way to the triple-helical “Madras” model of Ramachandran, which provided an essentially correct model of the molecule’s quaternary structure[47][48][49] although this model still required some refinement.[50] [clarification needed] [51][52][53][54] The packing structure of collagen has not been defined to the same degree outside of the fibrillar collagen types, although it has been long known to be hexagonal or quasi-hexagonal.[25][55][56] As with its monomeric structure, several conflicting models alleged that either the packing arrangement of collagen molecules is ‘sheet-like’ or microfibrillar.[50][57][58] The microfibrillar structure of collagen fibrils in tendon, cornea and cartilage has been directly imaged by electron microscopy.[59][60][61] The microfibrillar structure of tail tendon, as described by Fraser, Miller, and Wess (amongst others), was modeled as being closest to the observed structure,[50] although it oversimplified the topological progression of neighboring collagen molecules, and hence did not predict the correct conformation of the discontinuous D-periodic pentameric arrangement termed simply: the microfibril.[24][62] Various cross linking agents like L-Dopaquinone, embeline, potassium embelate and 5-O-methyl embelin could be developed as potential cross-linking/stabilization agents of collagen preparation and its application as wound dressing sheet in clinical applications is enhanced.[63]

See also

References

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  58. Jump up^ Wess, T. J.; Hammersley, AP; et al. (1998). “Molecular packing of type I collagen in tendon”. J Mol Biol 275 (2): 255–267. doi:10.1006/jmbi.1997.1449. PMID 9466908.
  59. Jump up^ Raspanti, M.; Ottani, V.; Ruggeri, A. (1990). “Subfibrillar architecture and functional properties of collagen: a comparative study in rat tendons”. J Anat. 172: 157–164.PMC 1257211. PMID 2272900.
  60. Jump up^ Holmes, D. F.; Gilpin, C. J.; Baldock, C.; Ziese, U.; Koster, A. J.; Kadler, K. E. (2001).“Corneal collagen fibril structure in three dimensions: Structural insights into fibril assembly, mechanical properties, and tissue organization”. PNAS 98 (13): 7307–7312.Bibcode:2001PNAS…98.7307H. doi:10.1073/pnas.111150598. PMC 34664.PMID 11390960.
  61. Jump up^ Holmes, D. F.; Kadler, KE (2006). “The 10+4 microfibril structure of thin cartilage fibrils”. PNAS 103 (46): 17249–17254. Bibcode:2006PNAS..10317249H.doi:10.1073/pnas.0608417103. PMC 1859918. PMID 17088555.
  62. Jump up^ Okuyama, K; Bächinger, HP; Mizuno, K; Boudko, SP; Engel, J; Berisio, R; Vitagliano, L (2009). “Comment on Microfibrillar structure of type I collagen in situ by Orgel et al. (2006), Proc. Natl Acad. Sci. USA, 103, 9001–9005”. Acta Crystallogr D Biol Crystallogr 65 (Pt9): 1009–10. doi:10.1107/S0907444909023051. PMID 19690380.
  63. Jump up^ Narayanaswamy, Radhakrishnan; Shanmugasamy, Sangeetha; Shanmugasamy, Sangeetha; Gopal, Ramesh; Mandal, Asit (2011). “Bioinformatics in crosslinking chemistry of collagen with selective crosslinkers”. BMC Research Notes 4: 399. doi:10.1186/1756-0500-4-399.

External links

12 types of collagen

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Illegal Drugs in Dietary Supplements

 drugs  Comments Off on Illegal Drugs in Dietary Supplements
May 132016
 

thumbnail image: Illegal Drugs in Dietary Supplements

Illegal Drugs in Dietary Supplements

Forbidden stimulant oxilofrine found in various dietary supplements sold in the USA

Read more

http://www.chemistryviews.org/details/news/9278771/Illegal_Drugs_in_Dietary_Supplements.html

 

 

Oxilofrine (also known as methylsynephrine, hydroxyephrine, oxyephrine, and 4-HMP) is a stimulant drug[1] and is anamphetamine chemically related to ephedrine and to synephrine.

Oxilofrine is currently a WADA prohibited substance when used in competition.[2] It is an ingredient found in some dietary supplements.

Publicized cases

  • In 2009, Brazilian/American cyclist Flávia Oliveira was suspended for 2 years after taking a supplement known as “HyperDrive 3.0+” which contained methylsynephrine, a chemical equivalent of Oxilofrine, among other substances. [3] Her sentence was eventually reduced to 18 months after an appeal as there was enough evidence that she had unknowingly consumed said substance as the old label did not list methylsynephrine.[4]
  • On July 14, 2013, Jamaican runners Asafa Powell and Sherone Simpson tested positive for Oxilofrine prior to the 2013 World Athletics Championships. [5] Powell, however, maintained that he did not take any banned supplements knowingly or willfully.[6]Powell voluntarily withdrew as a result of the test. On 10 April 2014, both athletes received an 18-month suspension from competing, which was set to expire in December that year.[7] However, after appealing to the Court of Arbitration for Sport (CAS), both athletes’ suspensions were lifted on 14 July 2014.[8]
  • On July 16, 2015, Boston Red Sox pitching prospect Michael Kopech was suspended without pay for 50 games after testing positive for Oxilofrine, which is a banned substance under the Minor League Drug Prevention and Treatment Program. Kopech denied knowingly taking the substance.[9]

 

 

 

 

References

  1.  Fourcroy, Jean L. (2008). Pharmacology, doping and sports: a scientific guide for athletes, coaches, physicians, scientists and administrators. Taylor & Francis. ISBN 978-0-415-42845-3.
  2.  http://list.wada-ama.org/prohibited-in-competition/prohibited-substances/
  3.  Charles Pelkey (2010-04-13). “Oliveira suspended for two years”. Velonews.
  4.  Charles Pelkey (2011-02-24). “Court of Arbitration for Sport reduces Flavia Oliveira suspension”. Velonews.
  5.  Reuters. “Jamaicans Powell, Simpson test positive – SuperSport – Athletics”. SuperSport. Retrieved 2013-07-15.
  6.  “Jamaican Sprinter Asafa Powell slapped 18-month ban for doping”. IANS. news.biharprabha.com. Retrieved 10 April 2014.
  7.  “Asafa Powell banned for 18 months for doping”. BBC Sport. 10 April 2014. Archived from the original on 9 May 2014.
  8.  Drayton, John (14 July 2014). “Asafa Powell and Sherone Simpson given green light to return to action after sprinters have doping bans reduced to six months”. Mail Online. Retrieved14 July 2014.
  9.  Danny Wild (16 July 2015). “Red Sox No. 10 prospect Kopech suspended”. MiLB.com. Retrieved 8 March 2016
Oxilofrine
Oxilofrin Structural Formulae V.1.svg
Systematic (IUPAC) name
(1S*,2R*)-(±)-4-(1-Hydroxy-2-methylamino-propyl)phenol
Legal status
Legal status
  • Uncontrolled
Identifiers
CAS Number 365-26-4 
ATC code none
PubChem CID 9701
ChemSpider 9320 Yes
UNII F49638UBDR Yes
KEGG D08314 Yes
ChEMBL CHEMBL30400 Yes
Chemical data
Formula C10H15NO2
Molar mass 181.23 g/mol

////Illegal Drugs, Dietary Supplements, Forbidden stimulant , oxilofrine, dietary supplements ,  USA, Oxilofrine

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APIs from Legitimate and Reliable Sources

 regulatory  Comments Off on APIs from Legitimate and Reliable Sources
May 122016
 

APIs from Legitimate and Reliable Sources

1. Introduction

Counterfeit and sub-standard APIs are increasingly present. Not only are they a fact of non-compliance but also they form a serious and increasing risk for patient safety. Various initiatives have been taken such as the founding of the FDA Counterfeit Drug Task Force, the European Commission’s current “Public consultation in preparation of a legal proposal to combat counterfeit medicines for human use” and the WHO Program “IMPACT” (International Medical Products Anti-Counterfeiting Taskforce).

API =Active pharmaceutical ingredient (synonym: drug substance)

Counterfeit API =Active pharmaceutical ingredient for which source and/or quality are falsely represented on the label, on the certificate of analysis or otherwise

Rogue API =API that is counterfeit or severely, deliberately non-compliant.

This writeup focuses on the interaction between the API manufacturer and the medicinal product manufacturer and provides possible measures that may be taken by both partners in order to ensure only non-rogue APIs are used in the manufacture of medicinal products. The proposed measures are considered as elements out of a whole puzzle. A risk-based approach should be applied to determine the necessity and value of the individual proposals, alone or in combination. The document does not address in detail the vendor qualification process as it is taken for granted that APIs are only purchased from suppliers that have been thorough checked

API manufacturer= Active pharmaceutical ingredient manufacturer

Medicinal product manufacturer= formulation manufacturer

Supply Chain

A supply chain is actually a complex and dynamicsupply and demand network. A supply chain is a system of organizations, people, activities, information, and resources involved in moving a product or service from supplier to customer.

2. Supply Chain:

Agents, Brokers, Distributors, Repackers, Relabelers As a general principle, the shorter the supply chain, the more secure it will be. This is reflected in the EU GMP Guidelines, Part 1 (5.26) specifying that starting materials (APIs, excipients) should be purchased, where possible, directly from the producer.

In addition to the length of the supply chain, any changes on the original container – e.g. by repackaging, relabeling – should be considered as an additional risk for alteration and should therefore, whenever possible, be avoided.

There is no doubt that the entire supply chain needs to be assessed from a quality perspective, covered by an effective supplier qualification program and the same principles as described in the following sections for the direct supply form API manufacturer to drug product manufacturer should be applied. This already starts at the point of selecting the contractor for transportation of the API (see also ICH Q7, 10.23).

 

 

3. On Site Visits / Audits

3.1.

Visits

A thorough knowledge of the supplier is a key element. Therefore, a close and stable relationship between the manufacturer of the API and the drug product manufacturer should be achieved by using various means of contact. A regular exchange between 3/8 sourcing- and purchasing people and the supplier contributes to strengthening this relationship, especially if the contact also includes regular visits on site. Site visits should not be restricted to the manufacturing site alone; intermediaries in the supply chain should be covered as well. It should be ensured that representatives of the purchasing department have a good GMP- and regulatory awareness and technical understanding so that these visits are as beneficial as possible, also in relation to compliance.

Audits=Auditing refers to a systematic and independent examination of books, accounts, documents and vouchers of an organization to ascertain how far the statements present a true and fair view of the concern.

3.2. Audits

An audit is considered the most effective way of verifying concrete and compliant manufacturing incl. distribution of APIs. However, apart from the fact that an audit is very time-consuming it only provides a snapshot of the situation and there is no 100% guarantee that evidence for any occurring counterfeiting activities may be identified. Nonetheless, there are various elements in a quality audit that may increase that probability and that respectively may confirm the reliability of the manufacturer.

Counterfeiting activities= To counterfeit means to imitate something. Counterfeit products are fake replicas of the real product. Counterfeit products are often produced with the intent to take advantage of the superior value of the imitated product

3.2.1 General

Whenever possible, the audit should be executed when an actual production campaign is ongoing.

Requests for changing the agenda at short notice during the audit, e.g. revisiting areas on another time or day, may be a useful approach to confirm the consistency of operations on site.

 

 

Warehouse=A warehouse is a commercial building for storage of goods. Warehouses are used by manufacturers, importers, exporters, wholesalers,transport businesses, customs, etc

3.2.2 Warehouse

The walk-through in the warehouse supports the verification of the materials management capability with respect to claimed annual production of the API and storage capacity.

Checking for the presence of intermediates or APIs in the warehouse that have been purchased and could be subject for relabeling or of APIs intended to undergo a reprocessing may lead to the identification of different sources of materials than claimed. The list of approved vendors should also be reviewed for this purpose.

The review of the materials management system and material movements (booking in/out) of concerned API starting materials, intermediates and the final API is another possible source of information in the warehouse. However, confidentiality with respect to other customers’ names needs to be respected.

Production=the action of making or manufacturing from components or raw materials, or the process of being so manufactured.

3.2.3 Production

The walk-through in production should cover the verification of the necessary equipment and necessary utilities by cross-checking with the production instruction and/or process flow chart.

 

 

Document Review=Document review (also known as doc review) is the process whereby each party to a case sorts through and analyzes the documents and data they possess (and later the documents and data supplied by their opponents through discovery) to determine which are sensitive or otherwise relevant to the case

3.2.4 Document Review

The review of master production instructions as well as analytical methods and specifications for raw materials, intermediates and the API as well as of executed documents/raw data and cross-checks with the regulatory document (e.g. DMF, CMC section, CEP dossier) is an important element in verifying regulatory compliance.

One can also verify the availability of production records and/or analytical raw data as well as retained samples (where applicable) of raw material, intermediates and API batches for specific batches that were either identified from the review of the stock cards/materials management system, product quality review or from supplied batches.

The timely and sequential correlation of equipment use logbooks in production and QC laboratory, production batch records (incl. electronic raw data), cleaning records and analytical raw data (incl. date/time on equipment printouts such as balances, chromatographic systems etc.) is a good indicator for on site production.

The review of the documentation related to seals (specifications – testing/approval according to specifications – reconciliation documentation – authorized persons identified and documented…) may be added.

A spot wise review of analytical raw data from stability studies (not only the summary table) as well as of the logbook of the stability chambers (e.g. date of sample in/out) and the check for physical availability of the stability samples should be included.

The adequate involvement of the drug product manufacturer in case of changes that can impact the quality and/or regulatory compliance of the API may be verified by the reviewing the history of changes and individual change request cases related to the production and testing of the API (incl. intermediates, raw materials),

4. Supporting Documentation

The availability of certain documents that are regularly available and up-dated, where applicable, may be considered as one efficient element in the continuous supplier monitoring process.

 

 

Inspections=Inspections are usually non-destructive. Inspections may be a visual inspection or involve sensing technologies such as ultrasonic testing, accomplished with a direct physical presence or remotely such as a remote visual inspection, and manually or automatically

4.1 Inspections,

Inspection history As part of the initial evaluation of a potential API supplier the GMP inspection history, with respect to inspecting regulatory body, inspection date, inspected areas (as far as this information is / is made available) and the inspection results should be reviewed. A regular up-date of the inspection history as part of the supplier monitoring and requalification process should be performed. On the other hand, as these inspections are not mandatory for APIs e.g. used in medicinal products for the EU, the non-availability of an inspection history may not lead to the conclusion that this API supplier is less reliable. 5/8

 

 

GMP=Good manufacturing practices (GMP) are the practices required in order to conform to the guidelines recommended by agencies that control authorization and licensing for manufacture and sale of food, drug products, and active pharmaceutical products. These guidelines provide minimum requirements that a pharmaceutical or a food product manufacturer must meet to assure that the products are of high quality and do not pose any risk to the consumer or public.

 

4.2 GMP certificates

GMP certificates of the API manufacturer, where available (see 4.1), should be provided, ideally as authentic copies.

 

 

Certificate of Analysis=A Certificate of Analysis is a document issued by Quality Assurance that confirms that a regulated product meets its product specification. They commonly contain the actual results obtained from testing performed as part of quality control of an individual batch of a product.

4.3 Certificate of Analysis

A thorough review of Certificate of Analysis, against regulatory documents (e.g. DMF, CMC section, CEP dossier) and in-house specification respectively, and with respect to GMP compliance (ICH Q7, 11.14) should be performed as part of incoming release testing of APIs. Suppliers involved in counterfeiting could apply improper documentation practices. In case of agents, brokers etc. being involved in the supply chain it is recommended to insist on a certificate of analysis issued by the original manufacturer of the API (see also 2.). Where a new certificate of analysis is prepared by agent, broker, distributor, there should be a reference to the name and address of the original manufacturer and a copy of the original batch Certificate should be attached, as specifically required by ICH Q7 11.43, 44

4.4 Certificate of Compliance,

Compliance Commitment A certificate of compliance issued by the API manufacturer, either as a separate document or as part of the certificate of analysis, which certifies that a specific batch has been manufactured according to ICH Q7 GMP requirements and in line with the applicable Registration Documents can provide additional assurance related to the awareness of the manufacturer on the quality and regulatory expectations of the customers.

4.5 On-going stability program

A GMP compliant manufacturer has an on-going stability program for its APIs (ICH Q7, 11.5). At least one batch of the API manufactured per year is added to the stability program and tested at least annually. A regular up-date of the program provided by the API manufacturer, not necessarily including stability data, gives additional assurance for actual and compliant systems.

4.6 Product Quality Review

The major objective of the Product Quality Review (ICH Q7, 2.5) is to evaluate the compliance status of the manufacture (process, packaging, labelling and tests) and to identify areas of improvement based on the evaluation of key data. It includes a review of critical in-process controls and critical API test results, of batches that failed to meet specification, of changes carried out, of the stability monitoring program, of quality-related returns/complaints/recalls and of the adequacy of corrective actions. Due to the comprehensive information included, the Product Quality Review provides a good overview of the manufacture of a certain API.

The document should be reviewed during an audit or as a minimum an approved executive summary should be made available by the API manufacturer.

4.7 Quality Agreement

The quality agreement as a tool to clearly define the GMP responsibilities strengthens the awareness of liabilities of both partners. The extent and level of detail of the agreement may vary and can depend on the material supplied, e.g. generic API versus exclusively synthesized API, but it should at least address – name of the product – mutually agreed specification (if not covered by supply agreement) – manufacturing site – applicable cGMP standards, e.g. ICH Q7 – compliance with the DMF or with other registration documentation – GMP audits related to the API (e.g. 3rd party auditing) – documents to be provided by the manufacturer, e.g. certificate of analysis, certificate of compliance, inclusion of copies of respective master documents may be addressed – arrangements for transportation and transport packaging (see 5.), e.g. description and degree of tampering proof seal to be used, inclusion of a copy of the master drum label may be considered – deviation handling – handling of and response to complaints – change management: involvement of the customer with respect to notification and approval – list of approved signatories may be included

 

5 Packaging:

labeling, tamper-proof sealing If the API manufacturer provides examples/templates of master labels, which he uses to label the containers, this supports the drug product manufacturer in identifying any manipulation on the material on its way from the manufacturer to the recipient.

The use of tamper-resistant packaging closure by the manufacturer provides additional assurance that the material was not adulterated on its way from the manufacturer to the drug product manufacturer. A manufacturer-specific design of the seal is recommended to be used; the use of unique seals may be considered. The communication of the type of seal, by the manufacturer to the user, completes the information chain.

Material Inspection = Critical appraisal involving examination, measurement, testing, gauging, and comparison of materials or items. An inspection determines if the material or item is in proper quantity and condition, and if it conforms to the applicable or specified requirements. Inspection is generally divided into three categories: (1) Receiving inspection, (2) In-process inspection, and (3) Final inspection. In quality control (which is guided by the principle that “Quality cannot be inspected into a product”) the role of inspection is to verify and validate the variance data; it does not involve separating the good from the bad.

Sampling= Sampling is the process of selecting units (e.g., people, organizations) from a population of interest so that by studying the sample we may fairly generalize our results back to the population from which they were chosen.

6. Material Inspection, Sampling, Analysis, Impurity Profile

At the point of receipt the first relevant action is to carefully perform the visual inspection of all the containers of the API. Attention shall be paid to the integrity and type of the sealing as well as to the special attributes added by the manufacturer (see above 4.7, 5.) such as label design, seal number and design.

The applied sampling regime related to the number of containers sampled, number of samples taken per container, analysis of individual and/or pooled samples as well as the extent of analysis, varying from identity test to full analysis may influence the probability of identifying counterfeiting, provided it may be identified by analytical means.

A risk-based approach, considering the qualification status of the supplier, may be chosen to define the extent of sampling and testing, considering the requirements for drug product manufacturers (e.g. Annex 8 to EU GMP Guidelines). 7/8 The impurity profile is normally dependent on the production process and origin of the API. The comparison of the impurity profile of a current batch with either previous batches or data provided by the manufacturer (e.g. as part of the regulatory submission) may help in order to identify changes related to modifications in the production process and may indicate whether the API might originate from a different manufacturer than the supposed one.

It is recommended to check the current (im)purity profile and compare it with former quality in regular intervals, at least once a year

 

DISCLAIMER

I , Dr A.M.Crasto is writing this blog to share the knowledge/views, after reading Scientific Journals/Articles/News Articles/Wikipedia. My views/comments are based on the results /conclusions by the authors(researchers). I do mention either the link or reference of the article(s) in my blog and hope those interested can read for details. I am briefly summarising the remarks or conclusions of the authors (researchers). If one believe that their intellectual property right /copyright is infringed by any content on this blog, please contact or leave message at below email address amcrasto@gmail.com. It will be removed ASAP

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USP publishes draft of a new general chapter <661.3> for plastic components used in manufacturing

 regulatory  Comments Off on USP publishes draft of a new general chapter <661.3> for plastic components used in manufacturing
May 122016
 

In the Pharmacopoeial Forum (PF)  42(3) (May-June 2016) the USP General Chapters – Packaging and Distribution Expert Committee proposes a new general chapter  <661.3> Plastic Components and Systems Used in Pharmaceutical Manufacturing and a revised version of general chapter <1661> Evaluation of Plastic Packaging and Manufacturing Systems and Their Materials of construction with Respect to Their User Safety Impact. Read more about USPs Proposal on Plastic Components and Systems Used in Pharmaceutical Manufacturing.

<1661> Evaluation of Plastic Packaging and Manufacturing Systems and Their Materials of construction with Respect to Their User Safety Impact. Read more about USPs Proposal on Plastic Components and Systems Used in Pharmaceutical Manufacturing.

see

http://www.gmp-compliance.org/enews_05341_USP-publishes-draft-of-a-new-general-chapter–661.3–for-plastic-components-used-in-manufacturing_15303,15493,Z-PKM_n.html

In the Pharmacopoeial Forum (PF)  42(3) (May-June 2016) the USP General Chapters – Packaging and Distribution Expert Committee proposes a new chapter to address the qualification of plastic components used in the manufacture of APIs (pharmaceutical and biopharmaceutical) and drug products (DPs). The proposed Title of the new chapter <661.3> is Plastic Components and Systems Used in Pharmaceutical Manufacturing. The draft is open for comment until July 31, 2016.

The chapter is part of a suite of chapters, including Plastic Packaging Systems and Their Materials of Construction <661>,Plastic Materials of Construction <661.1>, Plastic Packaging Systems for Pharmaceutical Use <661.2>, and Evaluation of Plastic Packaging and Manufacturing Systems and Their Materials of construction with Respect to Their User Safety Impact<1661>. In addition a section has been added to general chapter <1661> to support the use and understanding of the new general chapter <661.3>. The revision of general chapter <1661> (including change of title) also appears in the PF issue 42(3).

The chapter <661.3> addresses the qualification of plastic components used in pharmaceutical manufacturing and is applicable solely to those processes that involve liquid process streams and process intermediates due to the expected increased degree of interaction with liquids. Plastic manufacturing systems for pharmaceutical use include – for example – bags, cassettes, chromatographic columns, connectors, filling needles, filters, sensors, tanks, tubing, and valves.Elastomeric parts such as diaphragms, gaskets, and O-rings are not in the scope of this chapter. A flow diagram that shows a typical bioprocess DP production suite is shown in general chapter <1661>, Figure 2.

The manufacturer of APIs and DPs is responsible for ensuring that the plastic components and systems used are suited for the intended purpose. It is likely that raw materials, intermediates, process streams, APIs, and DPs will get in contact with one or more plastic component(s) of the manufacturing suite during the manufacturing process, resulting in process-related impurities (PrIs). PrIs have the potential to alter a quality attribute of the DP, if the PrIs persist through the manufacturing process.

Plastic manufacturing components and systems are chemically suited for their intended use with respect to safety if:

  • they are constructed from well-characterized materials that have been intentionally chosen for use as established by the test methods included in general chapter <661.1>;
  • The general physicochemical properties of the components have been established;
  • The biocompatibility (biological reactivity) has been appropriately established;
  • They have been established as safe by means of the appropriate chemical testing, such as extractables or leachables profiling and toxicological assessment of the test data (“chemical safety assessment”).

The chapter provides guidance on the appropriate application of biological reactivity tests (reference to general chapters <87>, <88>) and physicochemical tests (reference to Food Additive regulations and general chapter <661.1>, where applicable) for manufacturing components and systems. A two-stage approach consisting of an Initial Assessment followed by a Risk assessment leads to the required level of component characterization. The Initial Assessment examines the factors present for demonstration of equivalence with a comparator component or system by looking at the following parameters:

  • purpose and composition of component or system;
  • composition of DP(s);
  • processing conditions;
  • product dosage form.

The demonstration of equivalence would allow acceptance of the component (or system) without any further characterization. If equivalence cannot be established between the component (or system) under consideration and the comparator, then a Risk Assessment should be conducted. The risk assessment matrix is provided in detail in general chapter <1661>. The outcome of this assessment results in three risk levels: low (A), moderate (B), and high (C). These levels are linked according to the risk of the individual dosage form (e.g. solid oral and liquid oral, others than solid oral and liquid oral) to test requirements as shown in the draft chapter <661.3>. All three risk levels require identification of the component or system as specified in general chapter <661.1>. Identity is only required for those components or systems that consist of single materials of construction (individual polymers only). Biological reactivity testing according to USP general chapter <87> (In Vitro) is required for all levels plus testing according to Class VI in <88> (In Vivo) for Level B and C.  Level A and B require that the component or system be tested as specified in general chapter <661.1> for physicochemical characteristics and extractable metals characteristics. Level C components (or systems) must be characterized more rigorously than level A and B components in view of the extractables profile.
Additives: For level A components reference to 21 CFR Indirect Food Additive regulations is sufficient, for level B components additives are determined by testing, and for level C components extraction studies have to be performed.

After free registration in the Pharmarcopoeial Forum you can read the complete drafts of the new general chapter <661.3> and the revised chapter <1661>.

/////USP, draft,  new general chapter,  <661.3>, plastic components,  manufacturing

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EMA’s new Draft Guideline on the Sterilisation of Medicinal Products, APIs, Excipients and Primary Containers

 regulatory  Comments Off on EMA’s new Draft Guideline on the Sterilisation of Medicinal Products, APIs, Excipients and Primary Containers
May 122016
 

 

For medicinal products administrated in sterile form, the process to reduce the microbial level is a critical manufacturing step with regard to quality. The EMA has recently published the draft of a guideline on that topic which contains a range of clarifications. Read more about the coming requirements on sterilisation of medicinal products, APIs, excipients and final containers

see

http://www.gmp-compliance.org/enews_05350_EMA-s-new-Draft-Guideline-on-the-Sterilisation-of-Medicinal-Products–APIs–Excipients-and-Primary-Containers_15435,S-WKS_n.html

As referred to in the European Pharmacopoeia, the procedure for terminal sterilisation of a medicinal product, an API, or an excipient is generally the method of choice. Yet, this might be difficult in many cases for product stability reasons. That’s why other microbial reduction processes can be used like sterilising filtration or aseptic processing. So far, there has been some uncertainty about these methods and their acceptance in a marketing authorisation procedure or a variation application, and about which data have to be submitted.

EMA’s new draft guideline entitled “Guideline on the sterilisation of the medicinal product, active substance, excipient and primary container”  from April 2016 contains clear provisions with regard to the acceptance of alternative sterilisation processes by the European authorisation authorities. Those provisions apply to chemical and biological medicinal products for human and veterinary use as well as the respective APIs and excipients, but aren’t applicable for immunological veterinary medicinal products.

The document describes the requirements on sterilisation of medicinal products, APIs, excipients and primary containers, as well as on the choice of the method of sterilisation. Besides, the document contains two decision trees for the selection of the sterilisation method for products in diverse galenic forms.

Please find hereafter a summary of most important aspects in this chapter:

Manufacturing of sterile medicinal products
The conditions and physical parameters for the following processes are described in detail:

  • Steam sterilisation
  • Dry heat sterilisation
  • Ionisation radiation sterilisation (here reference is made to the Note for Guidance “The use of Radiation in the Manufacture for Medicinal Products“, ISO 11137 and Ph. Eur. Chapter 5.1.1)
  • Gas sterilisation (with ethylene oxide,  ethylene chlorhydrin, etc.)
  • Sterile filtration
  • Aseptic processing

Basically, the following rules apply to all processes:

  • The choice of the sterilisation method has to be justified.
  • The method must be validated.
  • The method described in the corresponding general monograph of the European Pharmacopoeia has to be used. All deviations have to be justified.
  • The procedures for all sites (including outsourced activities) where sterilisation is performed have to be documented (CTD module 3, chapters 3.2.P.2 and 3.2.P.3).

Manufacturing of sterile APIs and excipients
The document clarifies that the requirements laid down in Part II of the EU GMP Guide are only applicable for the manufacture beginning with the starting material up to the finished API, immediately prior to sterilisation. The sterilisation step performed on the API is considered to be a step in the manufacture of the medicinal product. As a consequence, each manufacturing establishment which performs sterilisation of an API requires a manufacturing authorisation, a GMP certificate and thus aQualified Person too. This also applies to establishments which manufacture sterile excipients. APIs and excipients with a Certificate of Suitability (CEP) are also covered by this regulation.

Selection of the sterilisation method
The following principles apply:

  • According to Ph. Eur., general chapter 5.1.1, the terminal sterilisation step should be made in the final container whenever possible.
  • When sterilisation by heat is not possible because of temperature sensitivity of the product, alternative methods or aseptic processing may be used if they are properly validated. Terminal steps for the reduction of the microbial level are also possible as long as they are not used to compensate for poor aseptic manufacturing practice.
  • A change (shortening) in shelf-life or storage conditions caused by the terminal sterilisation step is not in itself a reason to allow aseptic processing unless the new storage conditions or shelf-life would cause problems or restrictions in the use of the product.
  • An increase in impurity levels or degradation products upon terminal sterilisation doesn’t directly lead to the acceptation of aseptic processing. The risks induced by an increased level of impurities should be balanced with the risks induced with an aseptic manufacturing method (e.g. characteristics of the degradation products vs. posology of the medicinal product). Attempts performed to determine sterilisation conditions to give acceptable impurity levels and to simultaneously achieve a microbial reduction of at least 10-6 have to be described in the quality dossier.
  • Under specific conditions, aseptic processing may be accepted even if terminal sterilisation of the product itself would be possible, e.g. in the case of eye drops in polyethylene containers enabling administration of single drops or pre-filled pens. Here, terminal sterilisation of the product would destroy the final container.
  • The considerations for the choice of the container should be described in the dossier also in the case of heat-sensitive final containers. Here, the search for materials which come through terminal sterilisation has priority. For example, polypropylene is more resistant than polyethylene. The choice for the final container has to be justified.
  • Large volume parenterals should be terminally sterilised whenever possible.

In general, the regulatory authorities will expect a detailed justification for the selection of the sterilisation method or the aseptic processing in the form of a benefit/risk analysis.

The essence of the requirements described in the chapters of this guideline can be found in the two decision trees for sterilisation of products in diverse administration forms (aqueous liquid; non-aqueous liquid, semi-solid, dry powder).

The deadline for comments on this Draft Guideline Sterilisation of the medicinal product, active substance, excipient and primary container ends on October, 13th 2016.

///////////////EMA,  new Draft Guideline, Sterilisation of Medicinal Products, APIs, Excipients and Primary Containers

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Buthionine Sulphoximine

 Uncategorized  Comments Off on Buthionine Sulphoximine
May 112016
 

Skeletal formula of buthionine sulfoximine

Buthionine Sulphoximine

NDA Filed in china

A gamma-glutamylcysteine synthetase inhibitor potentially for the treatment of solid tumors.

 NSC-326231; BSO

CAS No. 5072-26-4

BUTHIONINE SULFOXIMINE; DL-Buthionine-[S,R]-sulfoximine; 5072-26-4; Buthionine sulfoxamine; Buthionine-S,R-sulfoximine; Buthione sulfoximine;

Molecular Formula: C8H18N2O3S
Molecular Weight: 222.30512 g/mol

Buthionine sulfoximine (BSO) is a sulfoximine which reduces levels of glutathione and is being investigated as an adjunct withchemotherapy in the treatment of cancer.[1] The compound inhibits gamma-glutamylcysteine synthetase, the enzyme required in the first step of glutathione synthesis. Buthionine sulfoximine may also be used to increase the sensitivity of parasites to oxidativeantiparasitic drugs.[2]

Buthionine sulphoximine is an oncolytic agent in early clinical development at the National Cancer Institute (NCI) for the treatment of neuroblastoma in pediatric patients in combination with melphalan and bone marrow or peripheral stem cell transplantation.

DATA

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1H NMR

 

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13C NMR

 

Synthesis

Methionine and buthionine sulfoximines: Syntheses under mild and safe imidation/oxidation conditions
Advanced Synthesis&Catalysis (2014), 356, (10), 2209-2213

Abstract

Thumbnail image of graphical abstract

Methionine and buthionine sulfoximines (MSO and BSO) are non-natural amino acids known to inhibit the biosynthesis of glutathione (GSH). The current syntheses of these biologically active molecules involve harsh reaction conditions and the use of hazardous reagents for the sulfur imidation. Here, improved syntheses of MSO and BSO are presented including safe and mild one-pot imidation/oxidation sequences and single-step deprotections of three different functionalities.

Methionine and Buthionine Sulfoximines: Syntheses under Mild and Safe Imidation/Oxidation Conditions

  1. Laura Buglioni,
  2. Vincent Bizet and
  3. Carsten Bolm*

DOI: 10.1002/adsc.201400354

http://onlinelibrary.wiley.com/doi/10.1002/adsc.201400354/abstract

References

  1.  Defty, CL; Marsden, JR (2012). “Melphalan in regional chemotherapy for locally recurrent metastatic melanoma.”. Current topics in medicinal chemistry 12 (1): 53–60. PMID 22196271.
  2.  “Definition of buthionine sulfoximine – National Cancer Institute Drug Dictionary”.

BUTHIONINE SULFOXIMINE.png

Buthionine sulfoximine
Skeletal formula of buthionine sulfoximine
Ball-and-stick model of buthionine sulfoximine as a zwitterion
Names
IUPAC name

2-amino-4-(butylsulfonimidoyl)butanoic acid
Other names

BSO
Identifiers
5072-26-4 
ChEBI CHEBI:28714 Yes
ChemSpider 19896 Yes
Jmol 3D model Interactive image
MeSH Buthionine+sulfoximine
PubChem 21157
Properties
C8H18N2O3S
Molar mass 222.305 g/mol
Density 1.29 g/mL
Melting point 215 °C (419 °F; 488 K)
Boiling point 382.3 °C (720.1 °F; 655.5 K)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

////NSC-326231,  BSO, 5072-26-4, Butionine sulfoximine, Neuroblastoma

CCCCS(=N)(=O)CCC(C(=O)O)N

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Multibiphenyl A, New biphenyls from Garcinia multiflora.

 Uncategorized  Comments Off on Multibiphenyl A, New biphenyls from Garcinia multiflora.
May 112016
 

Figure 2 Selected HMBC (H→C) and 1H-1H correlation spectroscopy (COSY) (–) correlations of 1. 

STR1

Compound 1 was obtained as a pale yellow gum. The molecular formula was determined to be C20H22O6 from the molecular ion peak [M]+ at m/z 358.1408 in the EI-HRMS. The IR spectrum indicated that 1 possesses hydroxy (3422 cm-1), phenyl (2939, 1498 cm-1), and carbonyl (1721 cm-1) functional groups. The 1H and 13C NMR spectra (Table 1) revealed the signals for a 1,2,3,4,5-pentasubstituted benzene ring [dH 6.26 (1H, s, H-6); δC 129.6 (C-1), 119.7 (C-2), 144.9 (C-3), 135.0 (C-4), 147.2 (C-5), 105.9 (C-6)], one p-substituted benzene ring [dH 7.00 (2H, dd, J 8.8, 2.4 Hz, H-8, H-12), 6.74 (2H, dd, J 8.8, 2.4 Hz, H-9, H-11); δC 133.8 (C-7), 131.7 (C-8, C-12), 115.7 (C-9, C-11), 157.1 (C-10)], one acetoxyprenyl group [dH 3.21 (2H, d, J 6.7 Hz, H-1′), 5.44 (1H, d, J6.7 Hz, H-2′), 4.33 (2H, s, H-4′), 1.39 (3H, s, H-5′), and 1.99 (3H, s, H-OAc); δC 26.8 (C-1′), 130.7 (C-2′), 134.6 (C-3′), 71.5 (C-4′), 14.0 (C-5′), 172.9, 20.8 (OAc)], and one methoxy group [dH 3.76 (3H, s, OMe-5); δC 56.5 (OMe)], which implied that compound1 was a biphenyl derivative. This conclusion was confirmed by the heteronuclear multiple bond correlation (HMBC) correlations of H-6 with C-7, and of H-8 and H-12 with C-1 (Figure 2). HMBC correlations of H-1′ with C-1, C-2, and C-3, and of H-2′ with C-1 suggested the acetoxyprenyl group at C-2. The methoxy group was located at C-5 from the HMBC correlations of δH 3.76 (OMe) with C-5. Considering the signal for quarternary C-3, C-4, C-10 and the molecular formula of 1, three hydroxy groups were located at C-3, C-4, C-10, respectively. Thus, the structure of 1 was determined as shown (Figure 1), and named multibiphenyl A.

Figure 1 New biphenyls from Garcinia multiflora. 

Multibiphenyl A (1)

Pale yellow gum; [α]D –11.0 (c 0.07, MeOH); UV (MeOH) lmax / nm (log ε) 570 (2.16), 205 (4.71); IR (KBr) n / cm-1 3422, 2939, 1721, 1611, 1589, 1498, 1443, 1357, 1266, 1172, 1102, 1045, 1023, 838; 1H and 13C NMR data (400 and 100 MHz, CD3OD), see Table 1; ESI-MS (positive mode) m/z 381 [M + Na]+; EI-HRMS (M+) calcd.: 358.1416; found: 358.1408 (C20H22O6).

Table 1 1H and 13C NMR data for compounds 1-3 (d in ppm, 1 and 2 in CD3OD, 3 in CDC13, 100 and 400 MHz) 

No. 1 2 3
δC (m) / ppm δH (m, J , Hz) / ppm δC (m) / ppm δH (m, J , Hz) / ppm δC (m) / ppm δH (m, J , Hz) / ppm
1 129.6 s 132.4 s 132.3 s
2 119.7 s 114.2 s 112.4 s
3 144.9 s 142.0 s 141.5 s
4 135.0 s 131.9 s 132.7 s
5 147.2 s 149.6 s 144.8 s
6 105.9 d 6.26 (s, 1H ) 106.6 d 6.44 (s, 1H) 105.5 d 6.43 (s, 1H)
7 133.8 s 134.6 s 132.7 s
8 131.7 d 7.00 (dd, 1H, J 8.8 Hz, 2.4) 131.8 d 7.11 (dd, 1H, J 8.4 Hz, 1.9) 130.3 d 7.16 (d, 1H, J 8.6 Hz)
9 115.7 d 6.74 (dd, 1H, J 8.8 Hz, 2.4) 116.0 d 6.82 (dd, 1H, J 8.4 Hz, 1.9) 114.8 d 6.86 (d, 1H, J 8.6 Hz)
10 157.1 s 157.7 s 155.5 s
11 115.7 d 6.74 (dd, 1H, J 8.8 Hz, 2.4) 116.0 d 6.82 (dd, 1H, J 8.4 Hz, 1.9) 114.8 d 6.86 (d, 1H, J 8.6 Hz)
12 131.7 d 7.00 (dd, 1H, J 8.8 Hz, 2.4) 131.8 d 7.11 (dd, 1H, J 8.4 Hz, 1.9) 130.3 d 7.16 (d, 1H, J 8.6 Hz)
1′ 26.8 t 3.21 (d, 2H, J 6.7 Hz, CH2) 124.7 d 6.41 (d, 1H, J 10.1 Hz) 21.1 t 2.59 (t, 2H, J 6.6 Hz, CH2)
2′ 130.7 d 5.44 (t, 1H, J 6.7 Hz) 124.4 d 5.48 (d, 1H, J 10.1 Hz) 33.0 t 1.72 (t, 2H, J 6.6 Hz, CH2)
3′ 134.6 s 77.6 s 74.7 s
4′ 71.5 t 4.33 (s, 3H, CH3) 69.0 t 4.27 (d, 1H, J 11.5 Hz, CH2) 26.7 q 1.39 (s, 3H, CH3)
4.14 (d, 1H, J 11.5 Hz, CH2)
5′ 14.0 q 1.39 (s, 3H, CH3) 23.4 q 1.47 (s, 3H, CH3) 26.7 q 1.39 (s, 3H, CH3)
3-OMe 56.5 q 3.76 (s, 3H, OCH3) 56.5 q 3.85 (s, 3H, OCH3) 56.1 q 3.86 (s, 3H, OCH3)
5′- OAc 172.9 s 172.6 s
20.8 q 1.99 (s, 3H, COCH3) 20.7 q 2.00 (s, 3H, COCH3)

Journal of the Brazilian Chemical Society

On-line version ISSN 1678-4790

J. Braz. Chem. Soc. vol.27 no.1 São Paulo Jan. 2016

http://dx.doi.org/10.5935/0103-5053.20150235

ARTICLES

New Biphenyls from Garcinia multiflora

Xue-Mei Gaoa  b  , Bing-Kun Jia  b  , Yin-Ke Lia  c  , Yan-Qing Yea  , Zhi-Yong Jianga  , Hai-Ying Yanga  , Gang Dua  , Min Zhoua  , Xiao-Xia Pana  , Wen-Xing Liua  , Qiu-Fen Hua  * 

aKey Laboratory of Chemistry in Ethnic Medicinal Resources, State Ethnic Affairs Commission & Ministry of Education, Kunming, P. R. China

bJoint Research Centre for International Cross-Border Ethnic Regions Biomass Clean Utilization in Yunnan, Yunnan Minzu University, 650031 Kunming, P. R. China

cCollege of Resource and Environment, Yuxi Normal University, 653100 Yuxi, P. R. China

ABSTRACT

Three new biphenyls were isolated from Garcinia multiflora. The structures of these biphenyls were elucidated by spectroscopic methods, and their rotavirus activity was evaluated.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532016000100010&lng=en&nrm=iso&tlng=en

Key words: Garcinia multiflora,  biphenyls,  anti-rotavirus activity

 

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Lupin to co-market Novartis’ asthma drug in India

 Uncategorized  Comments Off on Lupin to co-market Novartis’ asthma drug in India
May 112016
 

Lupin to co-market Novartis’ asthma drug in India

Business Standard

BS B2B Bureau  |  Mumbai April 12, 2016 Last Updated at 10:27 IST

Novartis Healthcare will continue to market Sequadra (indacaterol/glycopyrronium inhaler), while Lupin will promote the inhaler under the brand name Loftair in India

read original article at

http://www.business-standard.com/content/b2b-pharma/lupin-to-co-market-novartis-asthma-drug-in-india-116041200249_1.html

 

/////inhaler, Novartis Healthcare,  Sequadra, indacaterol, glycopyrronium inhaler,  Lupin,  inhaler,  brand name,  Loftair, India

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Ixorine, a New Cyclopeptide Alkaloid from the Branches of Ixora brevifolia

 Uncategorized  Comments Off on Ixorine, a New Cyclopeptide Alkaloid from the Branches of Ixora brevifolia
May 102016
 

Figure 2 Selected key HMBC (1H 13C) and NOESY (1H 1H) correlations for ixorine (1). 

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Figure 1 Structures of compounds 1–4 isolated from the branches of I. brevifolia. 

Ixorine (1)

HRESIMS m/z, calcd.: C30H40N4O4 [M + H]+: 521.3044; found: 521.3049; [α]D20 = -292.3 (c 0.001, CHCl3); 1H NMR (300 MHz, CDCl3) and 13C NMR (75 MHz, CDCl3), see Table 1.

Table 1 NMR spectroscopic data (300 MHz, CDCl3) for ixorine (1) 

Position δC δH (mult., J in Hz) HMBC COSY
1 156.3 − H-14, H-16 −
2 − − − −
3 81.7 4.91 (dd, 8.0, 2.1) H-4, H-18, H-19 H-4
4 55.6 4.44 (dd, 9.0, 8.0) − H-20 (NH)
5 171.6 − H-6 (NH) −
6 − 5.94 (d, 6.3, NH) − −
7 55.2 4.30 (m) H-28 H-28
8 167.2 − H-28 −
9 − 6.20 (sl, NH) − −
10 125.7 6.56 (m) − −
11 118.4 6.40 (d, 6.6) H-13 −
12 131.8 − H-14 −
13 131.7 7.03 (m) − H-14
14 121.9 7.15 (m) − −
15 122.7 7.03 (m) − H-16
16 130.2 6.92 (m) − −
17 29.3 2.00 (m) H-18, H-19 H-18, H-19
18 20.4 1.25 (d, 7.2) H-17, H-19 −
19 15.2 1.00 (d, 6.6) H-17 −
20 − 6.94 (m, NH) − −
21 172.4 − H-22, H-23 −
22 75.2 2.40 (d, 4.2) H-24, H-25, H-26, H-27 H-26, H-27
23 27.8 2.05 (m) H-24, H-25 H-24, H-25
24 21.0 1.05 (d, 6.9) − −
25 17.6 0.93 (d, 6.6) − −
26 43.1 2.14 (s) H-27 −
27 43.1 2.14 (s) − −
28 37.1 2.76 (dd, 13.8, 4.5)/3.07 (m) H-30, H-30’ H-28
29 135.7 − H-7, H-28, H-31, H-31’ −
30, 30’ 129.6 7.15 (m) − H-31, H-31’
31, 31’ 129.0 7.34 (m) − −
32 127.4 7.24 (m) − H-30, H-30’

 

Journal of the Brazilian Chemical Society

On-line version ISSN 1678-4790

J. Braz. Chem. Soc. vol.27 no.4 São Paulo Apr. 2016

http://dx.doi.org/10.5935/0103-5053.20150326

ARTICLES

Ixorine, a New Cyclopeptide Alkaloid from the Branches of Ixora brevifolia

Rebeca P. Medinaa  , Ivânia T. A. Schuquela  , Armando M. Pominia  , Cleuza C. Silvaa  , Cecília M. A. Oliveirab  , Lucília Katob  , Celso V. Nakamurac  , Silvana M. O. Santin*  a 

aDepartamento de Química, Universidade Estadual de Maringá, Av. Colombo 5790, 87020-900 Maringá-PR, Brazil

bInstituto de Química, Universidade Federal de Goiás, Campus II, Samambaia, 74001-970 Goiânia-GO, Brazil

cDepartamento de Análises Clínicas e Biomedicina, Universidade Estadual de Maringá, Av. Colombo 5790, 87020-900 Maringá-PR, Brazil

ABSTRACT

The isolation and structure determination of new cyclic peptide alkaloid ixorine, along with five known constituents frangulanine, syringaresinol, cinnamtannin B-1, daucosterol and mannitol from the branches of Ixora brevifolia are described. The cyclic peptide frangulanine is being described for the first time in the Rubiaceae family. The structures were elucidated on their spectral data basis, mainly one- (1H, 13C, DEPT) and two-dimensional (COSY, NOESY, HSQC and HMBC) nuclear magnetic resonance (NMR) and by comparison with data from the literature. The mixture of two cyclopeptide alkaloids showed weak activity against Leishmania amazonensis……..http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532016000400753&lng=en&nrm=iso&tlng=en

Key words: Ixora brevifolia,  Rubiaceae,  cyclopeptide alkaloids,  Leishmania

see……….http://www.scielo.br/pdf/jbchs/v27n4/0103-5053-jbchs-27-04-0753-suppl01.pdf

SUPPLEMENTARY INFORMATION

1D and 2D NMR spectra for compounds 1–2 are available free of charge online

0103-5053-jbchs-27-04-0753-suppl01.pdf

*e-mail: smoliveira@uem.br

////

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