Friday, 6 December 2013
AstraZeneca today announced that the European Commission (EC) has granted Marketing Authorisation to FluenzTM Tetra. Fluenz Tetra is a nasally administered four-strain live attenuated influenza vaccine for the prevention of influenza in children and adolescents from 24 months up to 18 years of age. The EC approval makes Fluenz Tetra the first and only intra-nasal four-strain influenza vaccine available in Europe.http://www.pharmalive.com/ec-approves-fluenz-tetra
(SARM-4, S-4), GTx-007
Acetamidoxolutamide
Androxolutamide
401900-40-1
WO 2002016310
Selective Androgen Receptor Modulators (SARM)
Signal Transduction Modulators
Andarine (GTx-007, S-4) is an investigational selective androgen receptor modulator (SARM) developed by GTX, Inc for treatment of conditions such as muscle wasting, osteoporosis and benign prostatic hypertrophy, using the non-steroidal androgen antagonist bicalutamide as a lead compound.
Androxolutamide is a nonsteroidal selective androgen receptor modulator (SARM) which had been in early clinical trials at GTx for the treatment of cancer-related cachexia in several cancer types; however, no recent development has been reported for this indication. Preclinical studies had also been ongoing for the treatment of osteoporosis due to androgen deficiency in the aging male. The drug candidate is believed to bind to the testosterone receptor in such a way as to maximize the beneficial effects of the hormone like muscle growth, bone strengthening and enhanced libido, while minimizing the unwanted side effects, such as stimulation of prostate cancer, virilization and acne. This is accomplished by the selective modulation of the androgen receptor depending on tissue type.
The compound was originally developed at GTx. In March 2004, GTx entered into a joint collaboration and license agreement with Ortho Biotech, a wholly-owned subsidiary of Johnson & Johnson; however, in 2006 the agreement was terminated by mutual agreement of the companies.
Andarine is an orally active partial agonist for androgen receptors. It is less potent in both anabolic and androgenic effects than other SARMs. In an animal model of benign prostatic hypertrophy, andarine was shown to reduce prostate weight with similar efficacy to finasteride, but without producing any reduction in muscle mass or anti-androgenic side effects. This suggests that it is able to competitively block binding of dihydrotestosterone to its receptor targets in the prostate gland, but its partial agonist effects at androgen receptors prevent the side effects associated with the anti-androgenic drugs traditionally used for treatment of BPH
Family: Selective Androgen Receptor Modulator
Half Life: About 4 hours
Formula: C19 H18 F3 N3 O6
Chemical Structure: S-3-(4-acetylamino-phenoxy)-2-hydroxy-2-methyl-N-(4-nitro-3-trifluoromethyl-phenyl)-propionamide
Anabolic Rating: Similar to Testosterone Propionate
Facts: Ostarine (*S-4) is a Selective Androgen Receptor Modulator produced by GTx Inc, which is currently in the investigational stages of development. A SARM is exactly what it sounds like: a compound (not an anabolic steroid) which has the ability to stimulate the androgen receptor (much the same way as anabolic steroids). Unfortunately, due to its status as a drug still in the developmental stage, most of the research on it has been done in rodents and trials only.
S-4 is an orally active (and highly bioavailable) selective agonist for androgen receptors which was shown to have anabolic effects in muscle and bone tissue. It has been shown to have no measurable effect on lutenizing hormone (LH) or follicle-stimulating hormone (FSH), but it has been shown to have some effect on prostate weight, with an androgenic potency around 1/3rd of its anabolic potency (1). Still, this is a good trade-off, because it’s anabolic effect has been measured to be roughly the same as testosterone. It has also been shown to produce dose-dependent increases in bone mineral density and mechanical strength in addition to being able decrease body fat and increase lean body mass (2).
Unfortunately, it has a short half-life in humans of only 4 hours (3), and thus far has only gone through phase II clinical testing in humans (4).
Practical Use: This compound has potential use for all aspects of male hormone replacement therapy, and could eventually replace testosterone for this purpose. Since there is currently no accepted test for SARMs, athletes who are subject to drug testing would find it to be a suitable replacement for anabolic steroid use. Since it doesn’t effect LH or FSH, it may also be a highly useful anabolic agent to be used while attempting post-cycle therapy.
Side Effects: Prostate enlargement (1/3rd of what is seen with testosterone) and potential acne are potential side effects, although most users don’t report either of them; much more common are vision problems (floaters, yellow-tinged vision). Water retention, gynecomastia, and most other steroid-related side effects are probably not possible. In addition, inhibition of natural hormone levels is probably minimal or nonexistent at worst.
Producing/Developing Company:
Ostarine by GTx Inc.
References:
The androgen receptor (′AR′″) is a ligand-activated transcriptional regulatory protein that mediates induction of male sexual development and function through its activity with endogenous androgens. Androgens are generally known as the male sex hormones. However, androgens also play a pivotal role in female physiology and reproduction. The androgenic hormones are steroids which are produced in the body by the testis and the cortex of the adrenal gland, or synthesized in the laboratory. Androgenic steroids play an important role in many physiologic processes, including the development and maintenance of male sexual characteristics such as muscle and bone mass, prostate growth, spermatogenesis, and the male hair pattern (Matsumoto, Endocrinol. Met. Clin. N. Am. 23:857-75 (1994). The endogenous steroidal androgens include testosterone and dihydrotestosterone (“DHT”) Testosterone is the principal steroid secreted by the testes and is the primary circulatiag androgen found in the plasma of males. Testosterone is converted to DHT by the enzyme 5 alpha-reductase in many peripheral tissues. DHT is thus thought to serve as the intracellular mediator for most androgen actions (Zhou, et al., Molec. Endocrinol. 9:208-18 (1995)). Other steroidal androgens include esters of testosterone, such as the cypionate, propionate, phenylpropionate, cyclopentylpropionate, isocarporate, enanthate, and decanoate esters, and other synthetic androgens such as 7-Methyl-Nortestosterone (“MENT′”) and its acetate ester (Sundaram et al., “7 Alpha-Methyl-Nortestosterone(MENT): The Optimal Androgen For Male Contraception,” Ann. Med., 25:199-205 (1993) (“Sundaram”)). Because the AR is involved in male sexual development and function, the AR is a likely target for effecting male contraception or other forms of hormone replacement therapy. The AR also regulates female sexual function (i.e., libido), bone formation, and erythropoiesis.
Worldwide population growth and social awareness of family planning have stimulated a great deal of research in contraception. Contraception is a difficult subject under any circumstances. It is fraught with cultural and social stigma, religious implications, and, most certainly, significant health concerns. This situation is only exacerbated when the subject focuses on male contraception. Despite the availability of suitable contraceptive devices, historically, society has looked to women to be responsible for contraceptive decisions and their consequences. Although health concerns over sexually transmitted diseases have made men more aware of the need to develop safe and responsible sexual habits, women still often bear the brunt of contraceptive choice. Women have a number of choices, from temporary mechanical devices such as sponges and diaphragms to temporary chemical devices such as spermicides. Women also have at their disposal more permanent options, such as physical devices like IUDs and cervical caps as well as more permanent chemical treatments, such as birth control pills and subcutaneous implants. However, to date, the only options available for men include the use of condoms or a vasectomy. Condom use, however is not favored by many men because of the reduced sexual sensitivity, the interruption in sexual spontaneity, and the significant possibility of pregnancy caused by breakage or misuse. Vasectomies are also not favored If more convenient methods of birth control were available to men, particularly long term methods that require no preparative activity immediately prior to a sexual act, such methods could significantly increase the likelihood that men would take more responsibility for contraception.
Administration of the male sex steroids (e.g., testosterone and its derivatives) has shown particular promise in this regard due to the combined gonadotropin-suppressing and androgen-substituting properties of these compounds (Steinberger et al, “Effect of Chronic Administration of Testosterone Enanthate on Sperm Production and Plasma Testosterone, Follicle Stimulating Hormones and Luteinizing Hormone Levels: A Preliminary Evaluation of a Possible Male Contraceptive”, Fertility and Sterility 28:1320-28 (1977)). Chronic administration of high doses of testosterone completely abolishes sperm production (azoospermia) or reduces it to a very low level (oligospermia). The degree of spermatogenic suppression necessary to produce infertility is not precisely known, However, a recent report by the World Health Organization showed that weekly intramuscular injections of testosterone enanthate result in azoospermia or severe oligospermia (i.e., less than 3 million sperm per ml) and infertility in 98% of men receiving therapy (World Health Organization Task Force on Methods Ar Regulation of Male Fertility, “Contraceptive Efficacy of Testosterone-Induced Azoospermia and Oligospermia in Normal Men,” Fertilily and Sterility 65:821-29 (1996)).
A variety of testosterone esters have been developed that are more slowly absorbed after intramuscular injection ancd, thus, result in greater androgenic effect. Testosterone enanthate is the most widely used of these esters. While testosterone enanthate has been valuable in terms of establishing the feasibility of hormonal agents for male contraception, it has several drawbacks, including the need for weekly injections and the presence of supraphysiologic peak levels of testosterone immediately following intramuscular injection (Wu, “Effects of Testosterone Enanthate in Normal Men: Experience From a Multicenter Contraceptive Efficacy Study,” Fertility and Sterility 65:626-36 (1996)).
“male drugs”. D. D. Miller, K. A. Veverka, and K. Chung report the large-scale synthesis of androgen-receptor modulators exemplified by 3a and 3b. These compounds have a variety of pharmaceutical applications related to male sex hormones, such as male contraceptives and drugs for treating prostate-related conditions. The inventors describe the kilogram-scale production of 3a and 3b by condensing 1 with 2a or 2b, as shown in Figure 1.
The reaction is carried out in the presence of a substantial excess of Cs2CO3 in THF. For the preparation of 3a, 6.17 mol Cs2CO3 is used with 3.37 mol 1; for 3b, 5.4 mol Cs2CO3and 2.7 mol 1 are used. (Disconcertingly, the patent shows the formula of the base as CsCO3, although the calculation of the molar amount is correct.) The preparation of 3atakes 3 h at 50 °C and is monitored by HPLC. TLC is used to monitor the synthesis of3b, which takes 8 h in refluxing THF.
To purify 3a, deionized water is added to an EtOH solution at room temperature to precipitate it; this process is repeated three times. The final yield of 3a is 83%. Purifying the product by using an alcohol and water is a key aspect of the patent and is covered in the claims. However, no analytical data are given to support the claimed purity. The workup of 3b also involves EtOH and water, but solvents EtOAc and MeO-t-Bu are also used; the product is isolated in 52% yield.
The inventors also describe the synthesis of compound 1 at kilogram scale (Figure 2). Acid chloride 5 is prepared by the reaction of carboxylic acid 4 with SOCl2. The acid chloride is not isolated, but it is treated with a solution of aniline derivative 6 and Et3N in THF over 3 h. After it is warmed to room temperature, the mixture is heated to 50 °C for 15 h. The reaction is monitored by TLC; 3.7 kg 1 is isolated by crystallization from warm toluene in 70.3% yield.
The multikilogram-scale synthesis of 4 is also described. The route, shown in Figure 3, starts with the preparation of compound 9 by simultaneously adding 4 M NaOH and a solution of acid chloride 8 in acetone to a mixture of carboxylic acid 7 and 4 M NaOH in acetone. The pH of the reaction mixture is kept at >10 by adding more 4 M NaOH as needed. Intermediate 9 is isolated by crystallization from MeO-t-Bu in 55.6% yield; it is then treated with N-bromosuccinimide (NBS) in DMF to cyclize it to 10. This is isolated in 87.7% yield by adding water to the reaction mixture. The final step is heating 10 to reflux in 24% aq HBr to produce 4, isolated as a crystalline solid from hot toluene in 81.3% yield.
The patent claims cover compounds related to 3a and 3b in which the nitro group is replaced by nitrile. Unfortunately, no examples are given describing the synthesis of these compounds. This is an efficient process for synthesizing 3a and 3b, and the inventors show that it is suitable for large-scale production. (University of Tennessee Research Foundation [Knoxville]. US Patent 7,968,721, June 28, 2011;
Novel pathway for the synthesis of arylpropionamide-derived selective androgen receptor modulator (SARM) metabolites of andarine and ostarine
TETRAHEDRON LETTERS,
Pages 2239-2242
Katharina M. Schragl, Guro Forsdahl, Guenter Gmeiner, Valentin S. Enev, Peter Gaertner
Vitamin D is an essential vitamin required by the body for the proper absorption of calcium, bone development, control of cell growth, neuromuscular functioning, proper immune functioning, and alleviation of inflammation. A deficiency in vitamin D can lead to rickets, a disease in which bones fail to properly develop. Further, inadequate levels of vitamin D can lead to a weakened immune system, increased cancer risk, poor hair growth, and osteomalacia, a condition of weakened muscles and bones. Conversely, excess vitamin D can cause the body to absorb too much calcium, leading to increased risk of heart attack and kidney stones. The current U.S. DV for vitamin D is 600 IU (international units) and the toxicity threshold for vitamin D is thought to be 10,000 to 40,000 IU/day.2 Vitamin D is oil soluble, which means you need to eat fat to absorb it. It is naturally found mainly in fish oils, fatty fish, and to a lesser extent in beef liver, cheese, egg yolks, and certain mushrooms. Vitamin D is also naturally made by your body when you expose your skin to the sun, and thus, is called the sun-shine vitamin. In addition, vitamin D is widely added to many foods such as milk and orange juice, and can also simply be consumed as a supplement. Below is a list of high vitamin D foods.
1: Cod Liver Oil
Cod liver oil has been a popular supplement for many years and naturally contains very high levels of vitamin A and vitamin D. Cod liver oil provides 10001IU (1667% DV) per 100 gram serving, or 1360IU (340% DV) in a single tablespoon.
2: Fish
Various types of fish are high in vitamin D. Typically raw fish contains more vitamin D than cooked, and fatty cuts will contain more than lean cuts. Further, fish canned in oil will have more vitamin D than those canned in water. Raw fish is typically eaten in the form of sushi. Raw Atlantic Herring provides the most vitamin D with 1628IU (271% DV) per 100 gram serving, 2996IU (499% DV) per fillet, and 456IU (76% DV) per ounce. It is followed by Pickled Herring with 680IU (113% DV) per 100g serving, Canned Salmon (127% DV), Raw Mackerel (60% DV), Oil Packed Sardines (45% DV), Canned Mackerel (42% DV), and oil packed Tuna (39% DV).
3: Fortified Cereals
A breakfast staple in the Americas, most commercial cereals are fortified with the essential vitamins and nutrients. Exercise caution and check food labels when purchasing cereals, be sure to pick products that have little or no refined sugars, and no partially hydrogenated oils! Fortified cereals can provide up to 342IU (57% DV) per 100 gram serving (~2 cups), and even more if combined with fortified dairy products or fortified soy milk. Products vary widely so be sure to check the nutrition label before buying.
4: Oysters
In addition to vitamin D, Oysters are a great source of vitamin b12, zinc, iron, manganese, selenium, and copper. Oysters are also high in cholesterol and should be eaten in moderation by people at risk of heart disease or stroke. Raw wild caught Eastern Oysters provide 320IU (80% DV) per 100 gram serving, 269IU (67% DV) in six medium oysters.
5: Caviar (Black and Red)
Caviar is a common ingredient in sushi and more affordable than people think. Caviar provides 232IU (58% DV) of vitamin D per 100 gram serving, or 37.1IU (9% DV) per teaspoon.
6: Fortified Soy Products (Tofu and Soy Milk)
Fortified soy products are often fortified with both vitamin D and calcium. Fortified Tofu can provide up to 157IU (39% DV) of vitamin D per 100 gram serving, or 44IU (11% DV) per ounce. Fortified Soy Milk can provide up to 49IU (12% DV) of vitamin D per 100 gram serving, 119IU (30% DV) per cup. Amounts of vitamin D vary widely between products, so be sure to check nutrition facts for vitamin D content.
7: Salami, Ham, and Sausages
Salami, Ham, and Sausages are a good source of vitamin b12, and copper. Unfortunately, they are also high in cholesterol and sodium, and so should be limited by people at risk of hypertension, heart attack, and stroke. Salami provides 62.0IU (16% DV) of vitamin D per 100 gram serving, or 16.7IU (4% DV) per ounce (3 slices). It is followed by Bologna Pork 56IU (9% DV) per 100 grams, and Bratwurst 44IU (7% DV) per 100 gram serving.
8: Fortified Dairy Products
Dairy products are already high in calcium, so it makes sense to fortify them with vitamin D. Milk can provide up to 52.0IU (13% DV) of vitamin D per 100 gram serving, 127IU (32% DV) per cup. Cheese can provide up to 6.6IU (2% DV) in a cubic inch, and butter provides 7.8IU (2% DV) in a single tablespoon. Check nutrition labels for exact amounts.
9: Eggs
In addition to vitamin D, eggs are a good source of vitamin B12, and protein. Eggs provide 37.0IU (9% DV) of vitamin D per 100 gram serving, or 17.0IU (4% DV) in a large fried egg.
10: Mushrooms
More than just a high vitamin D food, mushrooms also provide Vitamin B5 (Pantothenic Acid) and copper. Lightly cooked white button mushrooms provide the most vitamin D with 27.0IU (7% DV) per 100 gram serving, or 7.6IU (2% DV) per ounce.
(NaturalNews) Various cultures around the world already understand that herbs such as ginger, cinnamon, garlic and turmeric can effectively treat conditions like diabetes. According to research from the biomedical science department at the King Faisal University in Saudi Arabia, garlic may be the most powerful of them all for treating diabetes.
Learn more: http://www.naturalnews.com/042941_garlic_diabetes_treatment_oxidative_stress.html##ixzz2l5NBhJ00
865231-46-5 (AMG-837 free acid); 865231-45-4 (AMG-837 sodium salt)
(S)-3-(4-((4′-(trifluoromethyl)-[1,1′-biphenyl]-3-yl)methoxy)phenyl)hex-4-ynoic acid
Description of AMG-837: AMG-837 is a potent, orally bioavailable GPR40 agonist. AMG 837 was a potent partial agonist in the calcium flux assay on the GPR40 receptor and potentiated glucose stimulated insulin secretion in vitro and in vivo. Acute administration of AMG 837 lowered glucose excursions and increased glucose stimulated insulin secretion during glucose tolerance tests in both normal and Zucker fatty rats. The improvement in glucose excursions persisted following daily dosing ofAMG 837 for 21-days in Zucker fatty rats. Preclinical studies demonstrated that AMG 837 was a potent GPR40 partial agonist which lowered post-prandial glucose levels. These studies support the potential utility of AMG 837 for the treatment of type 2 diabetes. (PLoS One. 2011;6(11):e27270).
Current developer: Amgen Inc
A new versatile method for the iridium-catalyzed asymmetric substitution of racemic allylic alcohols is exemplified by the depicted synthesis of AMG 837, a GPR40 receptor agonist that is of interest for the treatment of type 2 diabetes.
The allylic alkynylation (27 examples) typically provides excellent branched-to-linear regioselectivity (rr > 50:1) and high enantioselectivity (≥99%). The scope of the allylic alkynylation was explored using 12 allylic alcohols and 15 potassium alkynyltrifluoroborates.
“Enantioselective Synthesis of a GPR40 Agonist AMG 837 via Catalytic Asymmetric Conjugate Addition of Terminal Alkyne to α,β-Unsaturated Thioamide”
Yazaki, R.; Kumagai, N.; Shibasaki, M.
Org. Lett. 2011, 13, 952. highlighted by Synfacts 2011, 6, 586.
PAPER
Scheme 18 Optimized preparation of biphenyl 54.
Scheme 17 Original Suzuki reaction employed for the synthesis of biphenyl 54.
http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532014001202186
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(R)-3-(2,3-Dihydroxypropyl)-6-fluoro-5-(2-fluoro-4-iodophenylamino)-8-methylpyrido[2,3-d]pyrimidine-4,7(3H,8H)-dione
| Molecular Weight: | 504.23 |
| TAK-733 Formula: | C17H15F2IN4O4 |
| CAS Number: | 1035555-63-5 |
TAK-733 is an orally bioavailable small-molecule inhibitor of MEK1 and MEK2 (MEK1/2) with potential antineoplastic activity. MEK inhibitor TAK-733 selectively binds to and inhibits the activity of MEK1/2, preventing the activation of MEK1/2-dependent effector proteins and transcription factors, which may result in the inhibition of growth factor-mediated cell signaling and tumor cell proliferation. MEK1/2 (MAP2K1/K2) are dual-specificity threonine/tyrosine kinases that play key roles in the activation of the RAS/RAF/MEK/ERK pathway and are often upregulated in a variety of tumor cell types.
BRAF L597 mutations in melanoma are associated with sensitivity to MEK inhibitors.
Dahlman et al. Cancer Discov. 2012 Jul 13. PMID: 22798288.Discovery of TAK-733, a potent and selective MEK allosteric site inhibitor for the treatment of cancer.
Dong et al. Bioorg Med Chem Lett. 2011 Mar 1;21(5):1315-9. PMID: 21310613.
MEK kinases regulate the pathway that mediates proliferative and anti-apoptotic signaling factors that promote tumor growth and metastasis. TAK-733 is an MEK kinase inhibitor that entered phase I clinical trials for the treatment of cancer. A noteworthy feature of this short synthesis (25% yield overall) is the one-pot, three-step synthesis of the fluoropyridone D, in which the fluorine atom is present at the outset.
The reaction of F with the nosylate G gave a mixture of N- and O-alkylation products (8:1) from which the desired N-alkylation product was isolated by crystallization. The mixture of N-methyl pyrrolidine (NMP) and methanol used in the final deprotection step, helped to ensure formation of the desired polymorph. The nine-step discovery synthesis (3% overall yield) is also presented.
Biopharmaceutical firm Zalicus has started a Phase Ib clinical trial of Z944, a novel oral T-type calcium channel blocker, for the treatment of neuropathic pain.
The company expects to release the results from the laser-evoked potentials (LEP) study in the fourth quarter of 2013.
The study is designed to offer both objective and subjective data on a drug’s ability to modulate pain signalling.
Z944 is a novel, oral, T-type calcium channel modulator that we are developing for pain.
Z944 is a novel, oral, state-dependent, selective T-type calcium channel modulator that has demonstrated efficacy in multiple preclinical inflammatory pain models and in a Phase 1b experimental model of pain. T-type calcium channels have been recognized as key targets for therapeutic intervention in a broad range of cell functions and have been implicated in pain signaling. Zalicus is planning to advance a modified release formulation of Z944 through further clinical development.
The wide distribution of T-type calcium channels found in brain, heart, endocrine cells and other tissues provides the possibility of developing therapeutics for multiple indications, including treatment of pain. Zalicus has utilized its expertise in this field to successfully discover high affinity, selective and orally available compounds, such as Z944, that show promise for further development.
T-type, or transient-type (referring to the length of time activated), calcium channel modulators target low-voltage-activated, calcium channels. These channels have been recognized as critical components in numerous cell functions and have been implicated in the frequency and intensity of pain signals. Zalicus is investigating compounds to modulate T-type calcium channel signaling in the treatment of pain. Our orally-administered T-type calcium channel blockers have shown efficacy in animal models of acute, chronic and visceral pain, as well as other indications.
patent
WO2009146540
http://www.google.com/patents/WO2009146540A1
compd may be
N-[1-(N-tert-Butylcarbamoylmethyl)piperidin-4-ylmethyl]-3-chloro-5-fluorobenzamide
http://cen.acs.org/articles/91/i45/Improving-Drug-Delivery.html
Nanoparticles are promising cargo ships for targeted drug delivery. But the materials have had limited success treating cancer, because they often can’t penetrate deep into tumors. The nanoparticles are stalled by the extracelluar matrix and compressed blood vessels.
http://cen.acs.org/articles/91/i45/Improving-Drug-Delivery.html
TAMOXIFEN
10540-29-1 CAS
READ ABOUT TITLE AT……….http://www.rsc.org/chemistryworld/sites/default/files/CIIE_Tamoxifen.mp3
Molecular Formula: C26H29NO•C6H8O7
CAS Number: 54965-24-1
Brands: Nolvadex, TAMOXIFEN CITRATE
Chemically, NOLVADEX (tamoxifen citrate) is the trans-isomer of a triphenylethylene derivative. The chemical name is (Z)2-[4-(1,2-diphenyl-1-butenyl) phenoxy]-N, N-dimethylethanamine 2 hydroxy-1,2,3- propanetricarboxylate (1:1). The structural and empirical formulas are:
 |
Tamoxifen citrate has a molecular weight of 563.62, the pKa’ is 8.85, the equilibrium solubility in water at 37°C is 0.5 mg/mL and in 0.02 N HCl at 37°C, it is 0.2 mg/mL.
NDA021807 APPR2005-10-29 DARA BIOSCIENCES,
| SOLTAMOX |
US PATENT 6,127,425
| US 6127425 | APPROVED 1998-06-26 | EXPIRY 2018-06-26 |
Tamoxifen is an antagonist of the estrogen receptor in breast tissue via its active metabolite, hydroxytamoxifen. In other tissues such as the endometrium, it behaves as an agonist, and thus may be characterized as a mixed agonist/antagonist. Tamoxifen is the usual endocrine (anti-estrogen) therapy for hormone receptor-positive breast cancer in pre-menopausal women, and is also a standard in post-menopausal women although aromatase inhibitors are also frequently used in that setting.
Some breast cancer cells require estrogen to grow. Estrogen binds to and activates the estrogen receptor in these cells. Tamoxifen is metabolized into compounds that also bind to the estrogen receptor but do not activate it. Because of this competitive antagonism, tamoxifen acts like a key broken off in the lock that prevents any other key from being inserted, preventing estrogen from binding to its receptor. Hence breast cancer cell growth is blocked.
Tamoxifen was discovered by pharmaceutical company Imperial Chemical Industries (now AstraZeneca) and is sold under the trade names Nolvadex, Istubal, and Valodex. However, the drug, even before its patent expiration, was and still is widely referred to by its generic name “tamoxifen.
Tamoxifen is currently used for the treatment of both early and advanced ER+ (estrogen receptor positive) breast cancer in pre- and post-menopausal women.Additionally, it is the most common hormone treatment for male breast cancer. It is also approved by the FDA for the prevention of breast cancer in women at high risk of developing the disease. It has been further approved for the reduction of contralateral (in the opposite breast) cancer.
In 2006, the large STAR clinical study concluded that raloxifene is equally effective in reducing the incidence of breast cancer, but after an average 4-year follow-up there were 36% fewer uterine cancers and 29% fewer blood clots in women taking raloxifene than in women taking tamoxifen, although the difference is not statistically significant.
Nolvadex (tamoxifen) 20 mg tablets
In 2005, the ATAC trial showed that after average 68 months following a 5 year adjuvant treatment, the group that received anastrozole (Arimidex) had significantly better results than the tamoxifen group in measures like disease free survival, but no overall mortality benefit. Data from the trial suggest that anastrozole should be the preferred medication for postmenopausal women with localized breast cancer that is estrogen receptor (ER) positive.Another study found that the risk of recurrence was reduced 40% (with some risk of bone fracture) and that ER negative patients also benefited from switching to anastrozole.
Crystallographic structure of 4-hydroxy-tamoxifen (carbon = white, oxygen = red, nitrogen = blue) complexed with ligand binding domain of estrogen receptor alpha (cyan ribbon)
Tamoxifen
Adequate patent protection is required to develop an innovation in a timely manner. In 1962, ICI Pharmaceuticals Division filed a broad patent in the United Kingdom (UK) (Application number GB19620034989 19620913). The application stated, “The alkene derivatives of the invention are useful for the modification of the endocrine status in man and animals and they may be useful for the control of hormone-dependent tumours or for the management of the sexual cycle and aberrations thereof. They also have useful hypocholesterolaemic activity”.
This was published in 1965 as UK Patent GB1013907, which described the innovation that different geometric isomers of substituted triphenylethylenes had either oestrogenic or anti-oestrogenic properties. Indeed, this observation was significant, because when scientists at Merrell subsequently described the biological activity of the separated isomers of their drug clomiphene, they inadvertently reversed the naming. This was subsequently rectified.
Although tamoxifen was approved for the treatment of advanced breast cancer in post-menopausal women in 1977 in the United States (the year before ICI Pharmaceuticals Division received the Queen’s Award for Technological Achievement in the UK), the patent situation was unclear. ICI Pharmaceuticals Division was repeatedly denied patent protection in the US until the 1980s because of the perceived primacy of the earlier Merrell patents and because no advance (that is, a safer, more specific drug) was recognized by the patent office in the United States. In other words, the clinical development advanced steadily for more than a decade in the United States without the assurance of exclusivity. This situation also illustrates how unlikely the usefulness of tamoxifen was considered to be by the medical advisors to the pharmaceutical industry in general. Remarkably, when tamoxifen was hailed as the adjuvant endocrine treatment of choice for breast cancer by the National Cancer Institute in 1984, the patent application, initially denied in 1984, was awarded through the court of appeals in 1985. This was granted with precedence to the patent dating back to 1965! So, at a time when world-wide patent protection was being lost, the patent protecting tamoxifen started a 17 year life in the United States. The unique and unusual legal situation did not go uncontested by generic companies, but AstraZeneca (as the ICI Pharmaceuticals Division is now called) rightly retained patent protection for their pioneering product, most notably, from the Smalkin Decision in Baltimore, 1996. (Zeneca, Ltd. vs. Novopharm, Ltd. Civil Action No S95-163 United States District Court, D. Maryland, Northern Division, March 14, 1996.)
Step 2.
Step 3.
Step 4.
Step 5.
step 6.
Synthetic Route 2: A Stereospecific Approach.
Stereospecific Synthesis of (Z) – Tamoxifen via carbometalation of Alkynylsilanes.
Studied for historical reasons rather than synthetic brilliance. This synthesis was the first stereo specific synthesis of (Z) Trans Tamoxifen. Comparison between this synthesis and the previous route I believe can illustrate the development of synthetic approaches to large molecules. In particular the quest for stereo specific reactions. So starting from an alkynylsilane (A) and through a series of reactions we can generate only the (Z) – Trans isomer of Tamoxifen.
Again for ease of understanding the complete synthesis has been broken down into a number of steps.
Step1.
Step1.
This step contains the vital stereo specific step. Namely the carbometalation of the alkynylsilane.It is this step which establishes the stereochemistry about the double bond. The phenyl (trimethyl silyl) – acetylene was carbometalated with diethylaluminium chloride – titanocene dichloride reactant to produce an organometallic intermediate. This organometallic intermediate was then cleaved with N bromosucciniamide to produce the alkene (B) in 85% yield.
The stereochemistry was assigned as E (Cis) mechanistic evidence suggests that this is linked to some steric reasons.
(Earlier work dedicated to this reaction see : Miller, R.B. Al-Hassan.M.I J.Org.Chem. 1984, 49, 725)
Step2.
Step 2.
The second step shows the stereo specific replacement of the Br group by a phenyl group. This was achieved by use of Palladium – catalysed coupling of compound (B) with phenyl zinc chloride to form (C) the vinylsilane in a 95% yield.
Step3.
Step3.
This step during the synthesis was reported to be tricky and several approaches were attempted before a successful technique was discovered.
The objective of this step was to replace the trimethyl Silyl group by a suitable halogen atom (e.g. Bromine or Iodine)
However a facile reaction was reported when (C) was treated with bromine – sodium methoxide at -78�C to produce the vinyl bromide (D) in a yield of 85%
Step 4.
Step 4.
The vinyl bromide (D) coupled well with a Zinc organometallic species to produce (E) the ethyl triaryl olefin in a yield of 84%.
Step 5.
Step 5.
The formation of (F) Tamoxifen was achieved by demethylation with sodium ethylthoilate in refluxing dimethyl formamide. then reaction of the phenoxide ion with 2-( dimethylamino)ethyl chloride via a SN2 substitution.
Purification of the crude product was achieved via it’s hydrochloride salt ( via a reaction with HCl (g)) then F was regenerated by treatment with dilute base this produced the stereospecific (Z)- Trans isomer in an overall yield of 60%.
http://pubs.rsc.org/en/content/articlelanding/2011/cs/c0cs00129e#!divAbstract
EP 0883587 A1 WO1997026234A1)
Preparation of Z isomer of Tamoxifen
A solution of bromobenzene (3.92g, 25mmol) in ether (5ml) containing a crystal of iodine was added dropwise to a suspension of magnesium turnings (0.63g, 26mmol) in ether (5ml) at reflux, under nitrogen. After the addition was complete, the reaction mixture was cooled to room temperature and a solution of l- [ 4- ( 2- chloroethoxy)phenyl]-2-phenyl-l-butanone (3.75g, 12.4mmol) in ether (15ml) was added over 1 hour. The resulting mixture was refluxed for 16 hours, then poured into dilute hydrochloric acid (50ml) and extracted with ether (3x40ml) . The combined ether layers were concentrated, the residual oil was dissolved in ethanol (10ml) and refluxed with concentrated hydrochloric acid (5ml) for 4 hours. The organic phase was separated, dried (Na2S04) and evaporated to dryness to give a yellow oil. Η NMR (see Figures 1 to 4 and discussion below) showed this to be a 2:1 mixture of the Z and E isomers. The oil was then dissolved in warm methanol (about 40°C) and allowed to cool to room temperature. The colourless crystals formed proved to be pure Z isomer of 2-chloroethoxy tamoxifen (4.12g, 11.4mmol, 92% yield) . M.p. 107-109°C, m/z 362/364 (chlorine atom present), <SH 0.92 (3H, t, J = 7.33 Hz, CH3) , 2.46 (2H, q, J = 7.33 Hz, CH2CH3) , 3.72 (2H, t, J = 5.86 Hz, 0CH2CH2C1) , 4.09 (2H, t, J = 5.86 Hz, 0CH2CH2C1) , 6.55 (2H, d, J = 8.79 Hz, aromatic protons ortho to 0CH2CH2C1) , 6.79 (2H, d, J = 8.79 Hz, aromatic protons meta to 0CH2CH2C1) , 7.10-7.38 (10H, m, the two remaining C6H5 ,s) (see Figure 5) . The 2-chloroethoxy tamoxifen was reacted with dimethylamine in ethanol, under reflux, to produce the desired Z isomer of tamoxifen.
Analysis of Η NMR data
Figures 1 to 4 represent a mixture of the E- and Z- forms of compound XI described above.
The expansion of the region ό* 0.80 to 1.05 shows two overlapping triplets corresponding to the CH3 groups in the
Z- and E- derivatives respectively. The critical point is the ratio of the heights of the peaks at 0.92 (for the Z) and 0.94 (for the E) , which is approximately 2:1. The expansion of the 4.00 to 4.35 region reveals similar information where ratios are 10:6.4 and 5.56:3.43.
Similarly expansion of the region 3.6 to 3.9 shows the ratio to be 2.46:1. All of these measurements suggest an approximate 2:1 ratio.
Referring to Figure 5, this shows almost pure Z- isomer. It should be noted that there is 660 mg of this from an original mixture of a 2:1 ratio mixture of 780 mg which would contain only 520 mg of the Z-isomer.
Z isomer of tamoxifen and 4-hydroxytamoxi en include stereoselective syntheses (involving expensive catalysts) as described in J. Chem. Soc, Perkin Trans I 1987, 1101 and J. Org. Chem. 1990, 55, 6184 or chromatographic separation of an E/Z mixture of isomers as described in J. Chem. Res., 1985 (S) 116, (M) 1342, 1986 (S) 58, (M) 771.
(Z)-tamoxifen (1) as a white solid, mp: 95.8-96.3 ºC. 1H-NMR (500 MHz, CDCl3) d 0.92 (3H, t, J 7.3 Hz), 2.29 (6H, s), 2.45 (2H, q, J 7.3 Hz), 2.65 (2H, t, J 5.8 Hz), 3.93 (2H, t, J 5.8 Hz), 6.68 (2H, d, J 9.5 Hz), 6.78 (2H, d, J 9.5 Hz), 7.08-7.28 (10H, m).13C-NMR (125 MHz, CDCl3) d 13.6 (CH3), 29.0 (CH2), 45.8 (CH3), 58.2 (CH2), 65.5 (CH2), 113.4 (C), 126.0 (C), 126.5 (CH), 127.8 (CH), 128.1 (C), 129.7 (C), 131.8 (CH), 135.6 (CH), 138.2 (CH), 141.3 (CH), 142.4 (CH), 143.8 (C), 156.7 (C). IR (KBr film) nmax/cm-1: 3055, 2979, 2925, 2813, 2769, 1606, 1509, 1240, 1035, 707. GC–MS (EI) m/z 371(5%), 58(100%).
(Z)-tamoxifen (1) and (E)-tamoxifen (2) in 52% yield. 1H-NMR (300 MHz, CDCl3) d 0.91 (Z isomer. 3H, t, J 7.3 Hz), 0.94 (E isomer. 3H, t, J 7.3 Hz), 2.28 (Z isomer. 6H, s), 2.34 (E isomer. 6H, s), 2.42-2.52 (Z and Eisomers. 4H, m), 2.63 (Z isomer. 2H, t, J 5.9 Hz), 2.74 (E isomer. 2H, t, J 5.9 Hz), 3.94 (Z isomer. 2H, t, J 5.9 Hz), 4.07 (E isomer. 2H, t, J 5.9 Hz), 6.68 (Z isomer. 2H, d, J 9.7 Hz), 6.76 (E isomer. 2H, d, J 9.3 Hz), 6.86-7.36 (Z and E isomers. 10H, m). IR (KBr film) nmax/cm-1: 3081, 3056, 2974, 2826, 2770, 1611, 1509, 1238, 1044. GC–MS (EI) m/z: Z isomer, 371(4%), 72 (24%), 58(100%); E isomer, 371(3%), 72 (24%), 58(100%). (the diastereoisomeric ratio was determined by capillary GC analysis and the configuration of the major diastereoisomer established by comparison of the NMR data of the synthetic mixture with an authentic sample of (Z)-tamoxifen (1).
nmr
ir
FTIR
shows the typical spectra’s of pure tamoxifen citrate, PCL, a physical mixture of tamoxifen citrate and PCL and drug-loaded implants. The spectrum of tamoxifen citrate shows characteristic absorption bands at 3027 cm−1 (=C-H stretching), 1507 and 1477 (C=C ring stretching) and 3180 cm -1 (-NH2). PCL displays a characteristic absorption band at strong bands such as the carbonyl stretching mode around 1727 cm−1 (C=O), asymmetric stretching 2949 cm−1 (CH 2 ) symmetric stretching 2865 cm−1 (CH 2 ). No changes in the spectrum of the physical mixture and drug-loaded microspheres were evident by FTIR spectroscopy. The strong bands such as the carbonyl peak were clear at all points.
 |
Figure 2: Transmission FTIR spectra of (a) tamoxifen-loaded implant, (b) physical mixture of drug+PCL, (c) pure PCL, (d) pure tamoxifen citrate |
enlarged view
FTIR spectra of A) tamoxifen citrate; B) PLGA; C) mixture of drug and excipients; D) freshly prepared nanoparticles in the formulation (BS-3HS).
Mentions: The pure drug tamoxifen citrate, PLGA-85:15, PVA, a mixture of PLGA and PVA, and a mixture of tamoxifen citrate, PLGA, and PVA; and a freshly prepared formulation were mixed separately with IR grade KBr in the ratio of 1:100 and corresponding pellets were prepared by applying 5.5 metric ton pressure with a hydraulic press. The pellets were scanned in an inert atmosphere over a wave number range of 4000–400 cm−1 in Magna IR 750 series II, FTIR instrument (Nicolet, Madison, WI, USA).
dsc
DSC thermograms of pure tamoxifen (a), pure PCL (b), physical mixture of drug+PCL (c) and (d) drug-loaded implant. The experiment was carried with crimped aluminum pans and a heating rate of 10ºC/min
xrd
X-ray diffraction studies of pure drug (a), pure PCL (b), physical mixture of drug+PCL (c) and (d) drug-loaded implant
synthesis
J.Chem. Research,1985(S) 116, (M) 1342 and 1986 (S) 58, (M) 0771.
TEVETEN® (eprosartan mesylate) is a non-biphenyl non-tetrazole angiotensin II receptor (AT1) antagonist. A selective non-peptide molecule, TEVETEN® is chemically described as the monomethanesulfonate of (E)-2-butyl-1 -(p-carboxybenzyl)-α-2-thienylmethylimid-azole-5 -acrylic acid.
Its empirical formula is C23H24N2O4S•CH4O3S and molecular weight is 520.625. Its structural formula is:
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EPROSARTAN MESYLATE
tevetenEprosartan mesilate, SK&F-108566-J(?, SK&F-108566, Teveten SB, Navixen, Regulaten, Tevetenz, Teveten
| US 5656650 | exp Aug 12, 2014 |
CAS EPROSARTAN
144143-96-4
133040-01-4
| Chemical Name: | Eprosartan mesylate |
| Synonyms: | EPROSARTAN MESYLATE;Eprosartan Methanesulfonate;4-[[2-butyl-5-(2-carboxy-3-thiophen-2-yl-prop-1-enyl)-imidazol-1-yl]methyl]benzoic acid mesylate;4-({2-butyl-5-[(1E)-2-carboxy-2-(thiophen-2-ylMethyl)eth-1-en-1-yl]-1H-iMidazol-1-yl}Methyl)benzoic acid;(E)-α-[[2-Butyl-1-[(4-carboxyphenyl)Methyl]-1H-iMidazol-5-yl]Methylene]-2-thiophenepropanoic Acid Methanesulfonate;(αE)-α-[[2-Butyl-1-[(4-carboxyphenyl)Methyl]-1H-iMidazol-5-yl]Methylene]-2-thiophenepropanoic Acid MonoMethanesulfonate |
| CBNumber: | CB4842192 |
| Molecular Formula: | C24H28N2O7S2 |
| Formula Weight: | 520.61832 |
Eprosartan is an angiotensin II receptor antagonist used for the treatment of high blood pressure. It is marketed as Teveten byAbbott Laboratories in the United States.It is marketed as Eprozar by INTAS Pharmaceuticals in India and by Abbott Laboratorieselsewhere. It is sometimes paired with hydrochlorothiazide, marketed in the US as Teveten HCT and elsewhere as TevetenPlus.
The drug acts on the renin-angiotensin system in two ways to decrease total peripheral resistance. First, it blocks the binding ofangiotensin II to AT1 receptors in vascular smooth muscle, causing vascular dilatation. Second, it inhibits sympatheticnorepinephrine production, further reducing blood pressure.
As with other angiotensin II receptor antagonists, eprosartan is generally better tolerated than enalapril (an ACE inhibitor), especially among the elderly.[1]
PAT APR EXP
| Canada | 2250395 | 2005-09-06 | 2017-03-26 |
| Canada | 2115170 | 2004-05-25 | 2012-08-12 |
| United States | 5656650 | 1994-08-12 | 2014-08-12 |
| United States | 5185351 | 1993-02-09 | 2010-02-09 |
| Canada | 2115170 | 2004-05-25 | 2012-08-12 |
| United States | 5656650 | 1994-08-12 | 2014-08-12 |
| Canada | 2250395 | 2005-09-06 | 2017-03-26 |
J Med Chem1991,34,(4):1514-7
J Med Chem1993,36,(13):1880-92
Synth Commun1993,23,(22):3231-48
AU 9056901, EP 403159, JP 91115278, US 5185351.
Drugs Fut1997,22,(10):1079
Eprosartan mesylate was developed successfully by SmithKline Beecham Corporation in 1997, and marketed in Germany in 1998 under the trade-name Teveten and in the United States later in 1999. Eprosartan mesylate, as an angiotensin II receptor blocker, is an antihypertensive drug of the latest generation. Eprosartan mesylate is potent to lower systolic and diastolic pressures in mild, moderate and severe hypertensive patients, and is safe and tolerable. Eprosartan mesylate is rapidly absorbed when administrated orally, with a bioavailability of 13% and a protein binding rate of 98%. The blood peak concentration and AUC (Area Under Curve) can be elevated by about 50% in patients with liver and kidney dysfunction, or fullness after administration, and can be elevated by 2 to 3 folds in elderly patients. Eprosartan mesylate has a structure shown as follows:
U.S. Pat. No. 5,185,351 discloses a method for preparing eprosartan mesylate using Eprosartan and methanesulfonic acid in isopropanol (U.S. Pat. No. 5,185,351, Example 41 (ii)). However, it is found when following this method for preparing eprosartan mesylate in industry, an esterification reaction can occur between eprosartan and isopropanol and the following two impurities can be generated:
In addition to the above two esterification impurities, the salifying method provided by the above patent is prone to produce isopropyl mesylate. Considering currently known potential risk of gene toxicity of methylsulfonic acid ester on human as well as the stringent requirements of methylsulfonic acid ester from the Europe and the America authorities, it is important to produce eprosartan mesylate in a non-alcohol solvent during the process of producing eprosartan mesylate, since it avoids the formation of methylsulfonic acid ester and the residue thereof in the final product. Since the dosage of eprosartan mesylate is high, it is particularly important to strictly control methylsulfonic acid ester in eprosartan mesylate.
In addition, for the above salifying method, solid eprosartan is suspended in propanol at a low temperature, then methanesulfonic acid is added, about ten seconds later a great deal of eprosartan mesylate precipitate is obtained. Therefore, solid eprosartan may be embedded by the precipitated eprosartan mesylate. Since isopropyl alcohol has a high viscosity at low temperature, a heavy filtering operation burden is needed to obtain solid from isopropanol, and the obtained solid contains quite an amount of isopropanol.
Eprosartan has been obtained by several different ways: 1) The iodination of 2-butylimidazole (I) with I2 and Na2CO3 in dioxane/water gives 2-butyl-4,5-diiodoimidazole (II), which is treated with benzyl chloromethyl ether (III) and K2CO3 in DMF yielding the imidazole derivative (IV). The condensation of (IV) with N-methyl-N-(2-pyridyl)formamide (V) by means of butyllithium in THF affords 1-(benzyloxymethyl)-2-butyl-4-iodoimidazole-5-carbaldehyde (VI), which is deprotected with concentrated HCl ethanol to give 2-butyl-4-iodoimidazole-5-carbaldehyde (VII). The acylation of (VII) with methyl 4-(bromomethyl)benzoate (VIII) by means of K2CO3 in hot DMF yields 4-(2-butyl-5-formyl-4-iodoimidazol-1 ylmethyl)benzoic acid methyl ester (IX), which is deiodinated by hydrogenation with H2 over Pd/C in methanol affording compound (X). The condensation of (X) with methyl 3-(2-thienyl)propionate (XI) by means of lithium diisopropylamide (LDA) in THF gives (XII), which is acylated with acetic anhydride and dimethylaminopyridine (DMAP) in dichloromethane yielding the corresponding acetate (XIII). Elimination of acetic acid from (XIII) with 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) in hot toluene affords the expected propenoic ester (XIV), which is finally saponified with NaOH or KOH in ethanol/water.
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WO 1998035962 A1
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