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MedKoo CAT#: 461088

CAS#: 118949-22-7

Description: Vorozole is a third-generation aromatase (cytochrome P450 19A1) inhibitor.

Price and Availability

Size Price Shipping out time Quantity
Inquire bulk and customized quantity

Pricing updated 2020-04-08. Prices are subject to change without notice.

Vorozole is not in stock, may be available through custom synthesis. For cost-effective reason, minimum 1 gram order is requested. The product will be characterized by NMR, HPLC and MS analysis. Purity (HPLC) is usually >98%. CoA, QC data, MSDS will be provided when product is successfully made. The estimated lead time is 2-3 months. Please send email to sales@medkoo.com to inquire quote.

Chemical Structure


Theoretical Analysis

MedKoo Cat#: 461088
Name: Vorozole
CAS#: 118949-22-7
Chemical Formula: C16H13ClN6
Exact Mass: 324.089
Molecular Weight: 324.77
Elemental Analysis: C, 59.17; H, 4.03; Cl, 10.92; N, 25.88

Synonym: Vorozole; R 83839; R-83839; R83839;

IUPAC/Chemical Name: 6-((4-chlorophenyl)(1H-1,2,4-triazol-1-yl)methyl)-1-methyl-1H-benzo[d][1,2,3]triazole


InChi Code: InChI=1S/C16H13ClN6/c1-22-15-8-12(4-7-14(15)20-21-22)16(23-10-18-9-19-23)11-2-5-13(17)6-3-11/h2-10,16H,1H3

SMILES Code: Cn1nnc2c1cc(C(n3ncnc3)c4ccc(Cl)cc4)cc2

Technical Data

Solid powder

>98% (or refer to the Certificate of Analysis)

Shipping Condition:
Shipped under ambient temperature as non-hazardous chemical. This product is stable enough for a few weeks during ordinary shipping and time spent in Customs.

Storage Condition:
Dry, dark and at 0 - 4 C for short term (days to weeks) or -20 C for long term (months to years).

Soluble in DMSO

Shelf Life:
>3 years if stored properly

Drug Formulation:
This drug may be formulated in DMSO

Stock Solution Storage:
0 - 4 C for short term (days to weeks), or -20 C for long term (months).

HS Tariff Code:


1: Raymond L, Rayani N, Polson G, Sikorski K, Lian A, VanAlstine-Parris MA. Determining the IC 50 Values for Vorozole and Letrozole, on a Series of Human Liver Cytochrome P450s, to Help Determine the Binding Site of Vorozole in the Liver. Enzyme Res. 2015;2015:321820. doi: 10.1155/2015/321820. Epub 2015 Nov 9. PubMed PMID: 26635974; PubMed Central PMCID: PMC4655258.

2: Biegon A, Alexoff DL, Kim SW, Logan J, Pareto D, Schlyer D, Wang GJ, Fowler JS. Aromatase imaging with [N-methyl-11C]vorozole PET in healthy men and women. J Nucl Med. 2015 Apr;56(4):580-5. doi: 10.2967/jnumed.114.150383. Epub 2015 Feb 19. PubMed PMID: 25698781.

3: Logan J, Kim SW, Pareto D, Telang F, Wang GJ, Fowler JS, Biegon A. Kinetic analysis of [11C]vorozole binding in the human brain with positron emission tomography. Mol Imaging. 2014;13:1-12. PubMed PMID: 24824855.

4: Pareto D, Biegon A, Alexoff D, Carter P, Shea C, Muench L, Xu Y, Fowler JS, Kim SW, Logan J. In vivo imaging of brain aromatase in female baboons: [11C]vorozole kinetics and effect of the menstrual cycle. Mol Imaging. 2013 Nov-Dec;12(8). doi: 10.2310/7290.2013.00068. PubMed PMID: 24447618.

5: Ozawa M, Takahashi K, Akazawa KH, Takashima T, Nagata H, Doi H, Hosoya T, Wada Y, Cui Y, Kataoka Y, Watanabe Y. PET of aromatase in gastric parietal cells using 11C-vorozole. J Nucl Med. 2011 Dec;52(12):1964-9. doi: 10.2967/jnumed.110.087072. Epub 2011 Nov 9. PubMed PMID: 22072705.

6: Wiseman LR, Spencer CM. Vorozole. Drugs Aging. 1997 Sep;11(3):245-50; discussion 251-2. Review. PubMed PMID: 9303282.

7: Takahashi K, Yamagishi G, Hiramatsu T, Hosoya A, Onoe K, Doi H, Nagata H, Wada Y, Onoe H, Watanabe Y, Hosoya T. Practical synthesis of precursor of [N-methyl-11C]vorozole, an efficient PET tracer targeting aromatase in the brain. Bioorg Med Chem. 2011 Feb 15;19(4):1464-70. doi: 10.1016/j.bmc.2010.12.057. Epub 2011 Jan 1. PubMed PMID: 21273085.

8: Harper-Wynne CL, Sacks NP, Shenton K, MacNeill FA, Sauven P, Laidlaw IJ, Rayter Z, Miall S, Howes A, Salter J, Hills MJ, Lowe FM, A'Hern R, Nasiri N, Doody D, Iqbal J, Dowsett M. Comparison of the systemic and intratumoral effects of tamoxifen and the aromatase inhibitor vorozole in postmenopausal patients with primary breast cancer. J Clin Oncol. 2002 Feb 15;20(4):1026-35. PubMed PMID: 11844826.

9: Wouters W, Snoeck E, De Coster R. Vorozole, a specific non-steroidal aromatase inhibitor. Breast Cancer Res Treat. 1994;30(1):89-94. Review. PubMed PMID: 7726994.

10: Goss PE. Pre-clinical and clinical review of vorozole, a new third generation aromatase inhibitor. Breast Cancer Res Treat. 1998;49 Suppl 1:S59-65; discussion S73-7. Review. PubMed PMID: 9797019.

11: Rissman EF, Harada N, Roselli CE. Effect of vorozole, an aromatase enzyme inhibitor, on sexual behavior, aromatase activity and neural immunoreactivity. J Neuroendocrinol. 1996 Mar;8(3):199-210. PubMed PMID: 8730654.

12: Wouters W, Van Ginckel R, Krekels M, Bowden C, De Coster R. Pharmacology of vorozole. J Steroid Biochem Mol Biol. 1993 Mar;44(4-6):617-21. PubMed PMID: 8386540.

13: Nephew KP, Osborne E, Lubet RA, Grubbs CJ, Khan SA. Effects of oral administration of tamoxifen, toremifene, dehydroepiandrosterone, and vorozole on uterine histomorphology in the rat. Proc Soc Exp Biol Med. 2000 Mar;223(3):288-94. PubMed PMID: 10719842.

14: Takahashi K, Onoe K, Doi H, Nagata H, Yamagishi G, Hosoya T, Tamura Y, Wada Y, Yamanaka H, Yokoyama C, Mizuma H, Takashima T, Bergström M, Onoe H, Långström B, Watanabe Y. Increase in hypothalamic aromatase in macaque monkeys treated with anabolic-androgenic steroids: PET study with [11C]vorozole. Neuroreport. 2011 May 11;22(7):326-30. doi: 10.1097/WNR.0b013e3283460282. PubMed PMID: 21460751.

15: Lubet RA, Steele VE, DeCoster R, Bowden C, You M, Juliana MM, Eto I, Kelloff GJ, Grubbs CJ. Chemopreventive effects of the aromatase inhibitor vorozole (R 83842) in the methylnitrosourea-induced mammary cancer model. Carcinogenesis. 1998 Aug;19(8):1345-51. PubMed PMID: 9744527.

16: Dowsett M, Doody D, Miall S, Howes A, English J, Coombes RC. Vorozole results in greater oestrogen suppression than formestane in postmenopausal women and when added to goserelin in premenopausal women with advanced breast cancer. Breast Cancer Res Treat. 1999 Jul;56(1):25-34. PubMed PMID: 10517340.

17: Goss PE, Winer EP, Tannock IF, Schwartz LH. Randomized phase III trial comparing the new potent and selective third-generation aromatase inhibitor vorozole with megestrol acetate in postmenopausal advanced breast cancer patients. North American Vorozole Study Group. J Clin Oncol. 1999 Jan;17(1):52-63. PubMed PMID: 10458218.

18: Kim SW, Biegon A, Katsamanis ZE, Ehrlich CW, Hooker JM, Shea C, Muench L, Xu Y, King P, Carter P, Alexoff DL, Fowler JS. Reinvestigation of the synthesis and evaluation of [N-methyl-(11)C]vorozole, a radiotracer targeting cytochrome P450 aromatase. Nucl Med Biol. 2009 Apr;36(3):323-34. doi: 10.1016/j.nucmedbio.2008.12.013. PubMed PMID: 19324278; PubMed Central PMCID: PMC3693459.

19: Takahashi K, Bergström M, Frändberg P, Vesström EL, Watanabe Y, Långström B. Imaging of aromatase distribution in rat and rhesus monkey brains with [11C]vorozole. Nucl Med Biol. 2006 Jul;33(5):599-605. Epub 2006 Jun 12. PubMed PMID: 16843834.

20: Diani-Moore S, Papachristou F, Labitzke E, Rifkind AB. Induction of CYP1A and cyp2-mediated arachidonic acid epoxygenation and suppression of 20-hydroxyeicosatetraenoic acid by imidazole derivatives including the aromatase inhibitor vorozole. Drug Metab Dispos. 2006 Aug;34(8):1376-85. Epub 2006 May 19. PubMed PMID: 16714371.