NIMBOLIDE

(From left to right) Principal Investigator Associate Professor Gautam Sethi and NUS PhD candidate Ms Zhang Jingwen from the Department of Pharmacology at the NUS Yong Loo Lin School of Medicine led a research which found that a bioactive compound from the neem plant could significantly suppress development of prostate cancer.

Credit: National University of Singapore

Date:September 29, 2016Source:National University of SingaporeSummary:Oral administration of nimbolide, over 12 weeks shows reduction of prostate tumor size by up to 70 per cent and decrease in tumor metastasis by up to 50 per cent, report investigators.

Nimbolide; NSC309909; NSC 309909; Methyl[8-(furan-3-yl)-2a,5a,6a,7-tetramethyl-2,5-dioxo-2a,5a,6,6a,8,9,9a,10a,10b,10c-decahydro-2h,5h-cyclopenta[d]naphtho[2,3-b:1,8-b'c']difuran-6-yl]acetate; CCRIS 5723;

CAS 25990-37-8;
Molecular Formula:	C27H30O7
Molecular Weight:	466.5229 g/mol

Oral administration of nimbolide, over 12 weeks shows reduction of prostate tumor size by up to 70 per cent and decrease in tumor metastasis by up to 50 per cent

A team of international researchers led by Associate Professor Gautam Sethi from the Department of Pharmacology at the Yong Loo Lin School of Medicine at the National University of Singapore (NUS) has found that nimbolide, a bioactive terpenoid compound derived from Azadirachta indica or more commonly known as the neem plant, could reduce the size of prostate tumor by up to 70 per cent and suppress its spread or metastasis by half.

Prostate cancer is one of the most commonly diagnosed cancers worldwide. However, currently available therapies for metastatic prostate cancer are only marginally effective. Hence, there is a need for more novel treatment alternatives and options.

“Although the diverse anti-cancer effects of nimbolide have been reported in different cancer types, its potential effects on prostate cancer initiation and progression have not been demonstrated in scientific studies. In this research, we have demonstrated that nimbolide can inhibit tumor cell viability — a cellular process that directly affects the ability of a cell to proliferate, grow, divide, or repair damaged cell components — and induce programmed cell death in prostate cancer cells,” said Assoc Prof Sethi.

Nimbolide: promising effects on prostate cancer

Cell invasion and migration are key steps during tumor metastasis. The NUS-led study revealed that nimbolide can significantly suppress cell invasion and migration of prostate cancer cells, suggesting its ability to reduce tumor metastasis.

The researchers observed that upon the 12 weeks of administering nimbolide, the size of prostate cancer tumor was reduced by as much as 70 per cent and its metastasis decreased by about 50 per cent, without exhibiting any significant adverse effects.

“This is possible because a direct target of nimbolide in prostate cancer is glutathione reductase, an enzyme which is responsible for maintaining the antioxidant system that regulates the STAT3 gene in the body. The activation of the STAT3 gene has been reported to contribute to prostate tumor growth and metastasis,” explained Assoc Prof Sethi. “We have found that nimbolide can substantially inhibit STAT3 activation and thereby abrogating the growth and metastasis of prostate tumor,” he added.

The findings of the study were published in the April 2016 issue of the scientific journal Antioxidants & Redox Signaling. This work was carried out in collaboration with Professor Goh Boon Cher of Cancer Science Institute of Singapore at NUS, Professor Hui Kam Man of National Cancer Centre Singapore and Professor Ahn Kwang Seok of Kyung Hee University.

Neem — The medicinal plant

The neem plant belongs to the mahogany tree family that is originally native to India and the Indian sub-continent. It has been part of traditional Asian medicine for centuries and is typically used in Indian Ayurvedic medicine. Today, neem leaves and bark have been incorporated into many personal care products such as soaps, toothpaste, skincare and even dietary supplements.

Future Research

The team is looking to embark on a genome-wide screening or to perform a large-scale study of proteins to analyse the side-effects and determine other potential molecular targets of nimbolide. They are also keen to investigate the efficacy of combinatory regimen of nimbolide and approved drugs such as docetaxel and enzalutamide for future prostate cancer therapy.

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Journal Reference:

1. Jingwen Zhang, Kwang Seok Ahn, Chulwon Kim, Muthu K. Shanmugam, Kodappully Sivaraman Siveen, Frank Arfuso, Ramar Perumal Samym, Amudha Deivasigamanim, Lina Hsiu Kim Lim, Lingzhi Wang, Boon Cher Goh, Alan Prem Kumar, Kam Man Hui, Gautam Sethi. Nimbolide-Induced Oxidative Stress Abrogates STAT3 Signaling Cascade and Inhibits Tumor Growth in Transgenic Adenocarcinoma of Mouse Prostate Model. Antioxidants & Redox Signaling, 2016; 24 (11): 575 DOI:10.1089/ars.2015.6418

A PAPER

NIMBOLIDE 1

http://pubs.rsc.org/en/content/articlelanding/2015/ra/c5ra16071e#!divAbstract

Nimbolide (1): Pale yellow crystals; C27H30O7;

FT-IR (KBr, υmax, cm -1): 2978, 1778, 1730, 1672, 1433, 1296, 1238, 1192, 1153, 1069, 951, 827, 750;

1H NMR (500 MHz, CDCl3) δH: 7.32 (t, J = 1.5 Hz, 1H), 7.28 (d, J = 9.5 Hz, 1H), 7.22 (s, 1H), 6.25 (m, 1H), 5.93 (d, J = 10.0 Hz, 1H), 5.53 (m, 1H), 4.62 (dd, J = 3.67 Hz, 12 .5 Hz, 1H), 4.27 (d, J = 3.5 Hz, 1H), 3.67 (d, J = 9.0 Hz, 1H), 3.54 (s, 3H), 3.25 (dd, J = 5.0 Hz, 16.25 Hz, 1H), 3.19 (d, J = 12.5 Hz, 1H), 2.73 (t, J = 5.5 Hz, 1H), 2.38 (dd, J = 5.5 Hz, 16.25 Hz, 1H), 2.22 (dd, J = 6.5 Hz, 12.0 Hz, 1H), 2.10 (m, 1H), 1.70 (s, 3H), 1.47 (s, 3H), 1.37 (s, 3H), 1.22 (s, 3H);

13C NMR (125 MHz, CDCl3) δC: 200.8 (CO), 175.0 (COO), 173.0 (COO), 149.6 (CH), 144.8 (C), 143.2 (CH), 138.9 (CH), 136.4 (C), 131.0 (CH), 126.5 (C), 110.3 (CH), 88.5 (CH), 82.9 (CH), 73.4 (CH), 51.8 (OCH3), 50.3 (C), 49.5 (CH), 47.7 (CH), 45.3 (C), 43.7 (C), 41.2 (CH2), 41.1 (CH), 32.1 (CH2), 18.5 (CH3), 17.2 (CH3), 15.2 (CH3), 12.9 (CH3);

HR-MS (m/z): 467.20795 [(M+H)+ ].

Content Page No 1 1H NMR spectrum of nimbolide S1 2 13C NMR spectrum of nimbolide S2 3 Mass spectrum of nimbolide

Dr Gautam Sethi

phcgs@nus.edu.sg
Tel.: (65)6516 3267
Fax: (65)6873 7690

Academic Qualifications
BSc. Chem. (Hons)	1998	Banaras Hindu University, Varanasi, India.
MSc. Biochemistry	2000	Banaras Hindu University, Varanasi, India.
Ph.D. Biotechnology	2004	Banaras Hindu University, Varanasi, India.
Appointments to Date
Assistant Professor	2008-date	Department of Pharmacology, National University of Singapore, Singapore
Postdoctoral Fellow	2004-2007	Department of Experimental Therapeutics, The University of Texas. MD Anderson Cancer Center, Houston TX USA.
Senior Research Fellow	2002-2004	(CSIR-NET) at School of Biotechnology, Banaras Hindu University, Varanasi, India.
Junior Research Fellow	2000-2002	(CSIR-NET) at School of Biotechnology, Banaras Hindu University, Varanasi, India.
Honours and Awards
2007	Ramalingaswamy fellowship from Department of Biotechnology, Government of India for outstanding research contributions in the field of Cancer Biology.
2002	Senior Research Fellowship award, Council of Scientific and Industrial Research, New Delhi, India.
2000	Junior Research Fellowship award, Council of Scientific and Industrial Research, New Delhi, India.
Research Interests
Selected Publications
Reviews and Book Chapters

/////////NIMBOLIDE, CANCER, NEEM, PROSTRATE, Gautam Sethi, National University of Singapore

CC1=C2C(CC1C3=COC=C3)OC4C2(C(C5(C6C4OC(=O)C6(C=CC5=O)C)C)CC(=O)OC)C

A simple scale-up strategy for organolithium chemistry in flow mode: From feasibility to kilogram quantities

Synthesis of 2-Trifluoromethyl-4-fluorophenylboronic acid (2a)
2a: 2-Trifluoromethyl-4-fluorophenylboronic acid After reaching steady-state, the outcoming stream was quenched for 25 min (765 mmol) on 797 mL citric acid (10% in water) at 0 °C. After full addition, the mixture was stirred for 30 min at 0 °C and then warmed up to r.t. and stirred for another hour. The phases were separated and the water phase was extracted twice with 1.8 L isopropyl acetate. The organic phases were combined, washed with 20% NaClsolution (1.8 L) and dried in vacuum to yield the final product. The product was obtained as a slightly yellow solid. 146.1 g (HPLC purity at 210 nm = 97.4%). Yield = 89%.

1H NMR (400 MHz, DMSO-d6): δ = 8.00 (dd, J = 8.3, 6.6 Hz, 1H, Ar-H), 7.52 (dd, J = 9.9, 2.5 Hz, 1H, Ar-H), 7.55−7.45 (m, 1H, Ar-H) ppm.

13C NMR (100 MHz, DMSO-d6): δ = 162.6 (d, J = 247.0 Hz, CF), 138.1 (d, J = 7.9 Hz), 134.8 (dq, J = 31.6, 7.7 Hz), 133.8, 124.5 (dq, J = 274.8, 3.00 Hz, CF3), 118.4 (d, J = 19.2 Hz), 113.3 (dq, J = 24.2, 6.1 Hz) ppm.

 19F NMR (376 MHz, DMSO-d6): δ = −57.8 (s, 3F, CF3), −111.2 (s, 1F, CF) ppm. 11B-NMR (128 MHz, DMSO-d6): δ = 13.8 ppm. Analytical data is identical with the literature.1 [1] A. Hafner, M. Meisenbach, J. Sedelmeier, Org. Lett. 2016, 18, 3630-3633.

A simple scale-up strategy for organolithium chemistry in flow mode: From feasibility to kilogram quantities Andreas Hafner, Paolo Filipponi, Lorenzo Piccioni, Mark Meisenbach, Berthold Schenkel, Francesco Venturoni and Joerg Sedelmeier* Novartis Pharma AG, Fabrikstrasse 14, 4002 Basel, Switzerland Joerg.Sedelmeier@novartis.com  

N-(5-amino-2-tert-butyl)-11-fluorbenzol[f]thiazol-[4,5-h]-quinazolin-10-yl)-2,6-difluorbenzolsulfonamide = Dabrafenib_photo (2)

C23H18F3N5O2S2 (Mr = 517.09)

Solution of 5 mg (9.6 μmol) dabrafenib in 2 ml THF was irradiated at 365 nm with 5.4 W for 2 min. This procedure was repeated 18 times at room temperature. The reaction batches were combined. The total initial weight of dabrafenib was 101 mg (190 μmol). The solvent was removed under reduced pressure and the residue was purified by the flash chromatography (SiO2 reversed phase, MeOH/water gradient 50:50 to 100:0) to give compound 2 as a yellowish solid (36.2 mg, 70.0 μmol, yield: 37%).

1H-NMR (DMSO-d6 , 300 MHz): δ = 1.52 (s, 9 H, H-8), 7.28 (m, 2 H, NH2), 7.28 (ddd, 5 J = 0.4 Hz, 4 J = 1.7 Hz, 3 J = 8.5 Hz, 3 J = 8.9 Hz, 2 H, H-18), 7.59 (dd, 3 J = 7.4 Hz, 3 J = 7.8 Hz, 1 H, H-13), 7.71 (tt, 4 J = 6.1 Hz, 3 J = 8.5 Hz, 1 H, H-19), 8.56 (dd, 4 J = 0.9 Hz, 3 J = 9.3 Hz, 1 H, H-14), 9.79 (s, 1 H, H-2), 11.01 (s, 1 H, NH) ppm.

13C-NMR (DMSO-d6 , 300 MHz): δ = 30.4 (s, C-8), 38.3 (s, C-7), 110.9 (d, 4 JCF = 1.6 Hz, C-3), 113.4 (dd, 2 JCF = 22.7 Hz, 2 JCH = 3.5 Hz, C-18), 114.6 (d, 3 JCF = 10.3 Hz, C-9), 117.4 (d, 2 JCF = 16.1 Hz, C-16), 117.6 (dd, 4 JCF = 0.54 Hz, 2 JCH = 4.4 Hz, C-13), 120.8 (d, 2 JCF = 12.3 Hz, C-10), 125.4 (s, C-13), 129.3 (d, 3 JCF = 3.9 Hz, C-15), 130.6 (s, C-5), 135.9 (tt, 3 JCF = 10.9 Hz, 2 JCH = 3.3 Hz, C-19), 148.8 (dd, 2 JCF = 0.54 Hz, 2 JCH = 7.2 Hz, C-12), 149.2 (s, C-4), 150.1 (s, C-11), 157.1 160.5 (dd, 3 JFF = 257.3 Hz, 2 JCF = 3.61 Hz, C-4), 157.9 (s, C-2), 162.1 (s, C-1), 184.0 (s, C-6) ppm.

15N-HMBC (DMSO-d6 , 300 MHz): δ = 9.79/-119.60, 11.01/-268.37 ppm. 19F-NMR (DMSO-d6 , 300 MHz): δ = -121.03 (s, 1 F, F-11), -107.18 (m, 2 F, F-17) ppm.

HRMS (EI, 205 °C, THF): m/z = 517.0849 [M]+ .

LC-MS (ESI, 70 eV, MeOH): tR = 9.3 min; m/z (%) = 518.1 (100) [M+H]+

IR (ATR):  ̃ = 3490 (N-H), 3176 (arom. C-H), 2926 (C-H3), 1696 (N=N), 1613 (N-H), 1587, 1522, 1488, 1469 (arom. C=C), 1342 (sulfonamide), 1277, 1240, 1174 (C-F) cm-1 .

Photoinduced Conversion of Antimelanoma Agent Dabrafenib to a Novel Fluorescent BRAFV600E Inhibitor

Boris Pinchuk, Thorsten von Drathen, Viktoria Opel, and Christian Peifer*

Institute of Pharmacy, University of Kiel, Gutenbergstr. 76, D-24118 Kiel, Germany

ACS Med. Chem. Lett., Article ASAP

DOI: 10.1021/acsmedchemlett.6b00340

Publication Date (Web): September 20, 2016

Copyright © 2016 American Chemical Society

*E-mail: cpeifer@pharmazie.uni-kiel.de. Tel: +49-431-880-1137.

ACS Editors' Choice - This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes.

http://pubs.acs.org/doi/full/10.1021/acsmedchemlett.6b00340

Abstract

Dabrafenib (Tafinlar) was approved in 2013 by the FDA as a selective single agent treatment for patients with BRAFV600E mutation-positive advanced melanoma. One year later, a combination of dabrafenib and trametinib was used for treatment of BRAFV600E/K mutant metastatic melanoma. In the present study, we report on hitherto not described photosensitivity of dabrafenib both in organic and aqueous media. The half-lives for dabrafenib degradation were determined. Moreover, we revealed photoinduced chemical conversion of dabrafenib to its planar fluorescent derivative dabrafenib_photo 2. This novel compound could be isolated and biologically characterized in vitro. Both enzymatic and cellular assays proved that 2 is still a potent BRAFV600E inhibitor. The intracellular formation of 2 from dabrafenib upon ultraviolet irradiation is shown. The herein presented findings should be taken in account when handling dabrafenib both in preclinical research and in clinical applications.

////////Photoinduced Conversion, Antimelanoma Agent,  Dabrafenib, Novel Fluorescent BRAFV600E Inhibitor, BRAFV600E; Dabrafenib, fluorescent probe,  kinase inhibitor,  photoinduced conversion

Mutianyu

Great Wall of China at Mutianyu.

Mutianyu

Mutianyu is a section of the Great Wall of China located in Huairou County 70 km northeast of central Beijing. The Mutianyu section of the Great Wall is connected with Jiankou in the west and Lianhuachi in the east. Wikipedia

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Olmesartan dimer

olmesartan dimer

Olmesartan Dimer Ester 

CAS No.

:

1040250-19-8

Molecular Weight

:

874.99

Molecular Formula

:

C48H50N12O5

A dimeric degradation product in stressed tablets of Olmesartan .;Impurity in commercial preparations of Olmesartan 

Synonyms

4-(1-Hydroxy-1-methylethyl)-2-propyl-1-[[2�-(2H-tetrazol-5-yl)[1,1�-biphenyl]-4-yl]methyl]-1H-imidazoleopyl-1-[[2�-(2H-tetrazol-5-yl) [1,1�-biphenyl]-4-yl]methyl]-1H-imidazol-4-yl]-1-methylethyl Ester; DP-1; 

References

Murakami, T., et al.: J. Pharma. Biomed. Anal., 47, 553 (2008), 

CN 104650046 



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A high-yielding method for the preparation of isoxazolopyridin-3-amine derivatives

A highly efficient and green method has been developed for the rapid preparation of highly functionalized isoxazolopyridin-3-amine derivatives in excellent yields. This process has a broad substrate scope, is operationally simple, and generally requires no chromatographic purification. In addition, the process is scalable and significantly greener than current alternatives with a PMI of 18 and water as the reaction solvent.

A rapid preparation of highly functionalized isoxazolopyridin-3-amine and other heterocyclic fused aminoisoxazole derivatives

A high-yielding method for the preparation of isoxazolopyridin-3-amine derivatives

Wensheng Yu,*^a   Paul G. Bulger^b and   Kevin M. Maloney*^b  

*

Corresponding authors

^a

Discovery Chemistry, Merck Research Laboratories, 126 E. Lincoln Avenue, Rahway, USA
E-mail: wensheng.yu@merck.com

^b

Process Chemistry, Merck Research Laboratories, 126 E. Lincoln Avenue, Rahway, USA

Green Chem., 2016,18, 4941-4946

DOI: 10.1039/C6GC01125J

http://pubs.rsc.org/en/Content/ArticleLanding/2016/GC/C6GC01125J?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+rss%2FGC+%28RSC+-+Green+Chem.+latest+articles%29#!divAbstract

Wensheng Yu

Associate Principal Scientist at Merck

Paul G. Bulger was born in London, England, in 1978. He received his undergraduate M.Chem degree in 2000 from the University of Oxford, completing his Part II project under the supervision of Dr. Mark G. Moloney. He remained at Oxford for his graduate studies, obtaining his D. Phil. in chemistry in 2003 for research conducted under the supervision of Professor Sir Jack E. Baldwin. After an enjoyable three-year stint as a postdoctoral researcher in Professor K. C. Nicolaou's group at The Scripps Research Institute, he joined the Process Research Department of Merck & Co., Inc. in the fall of 2006.






pic not available

Kevin Maloney

Sr Research Chemist at Merck Sharp & Dohme

Experience

Sr Research Chemist

Merck Sharp & Dohme

Sr Research Chemist

Merck

2007 – Present (9 years)

Education

Massachusetts Institute of Technology

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Chopda

Chopda is a city and a municipal council in Jalgaon district in the state of Maharashtra, India.

Chopda

City in India

Chopda is a city and a municipal council in Jalgaon district in the state of Maharashtra, India. Wikipedia

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