Synthesis of temozolomide and analogs

Inactive Publication Date: 2005-06-16
SCHERING CORP
View PDF1 Cites 11 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

[0016] Step (b) is preferably carried out by hydrolysis with a strong mineral acid such as concentrated HCl or HBr, or HClO4, CF3SO3H, or MeSO3H, or especially concentrated sulfuric acid, at a moderate temperature such as −20 to 50° C. In a particularly preferred embodiment, the readily-removable protecting group is a 1,1-dimethylethyl group (a t-butyl group), together with a hydrogen atom. Its bulk also helps to promote the correct direction of cyclization.

Problems solved by technology

However, this process requires isolation of the unstable and potentially dangerous 5-diazo-1H-imidazole-4-carboxamide (B).
Moreover, methylisocyanate is a difficult reagent to handle and ship, especially on the industrial scale, and indeed is better avoided in industrial manufacture.
Moreover, the unstable 5-diazo-1H-imidazole-4-carboxamide (B) still has to be isolated in the branch of this process that uses it as an intermediate.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Synthesis of temozolomide and analogs
  • Synthesis of temozolomide and analogs
  • Synthesis of temozolomide and analogs

Examples

Experimental program
Comparison scheme
Effect test

example 1

3-Methyl-8-aminocarbonvl-imidazo[5,1-d]-1,2,3,5-tetrazin-4(3H)-one (Temozolomide)

[0059] Step A: Preparation of 2-cvano-N-(1,1-dimethylethyl)-2-[(diphenylmethylene)amino]-acetamide

[0060] The imine 3 (700 g, 3.178 mol) and CH2Cl2 (7 L) were placed into a 22 L three-necked flask equipped with a nitrogen inlet, a gas outlet tube, reflux condenser, thermometer, mechanical stirrer, and maintained under a positive pressure of nitrogen. 1,1-Dimethylethyl-isocyanate (442 mL, 3.870 mol) was added to this stirred mixture at 0° C., and after stirring for 10 min a solution of potassium t-butoxide in THF (1.0 M in THF, 3.88 L, 3.88 mol) (as supplied by Aldrich) was added slowly (1 hour). The solution was stirred at 0° C. for 4 hours, when the reaction mixture had become a very thick paste with a deep brown color, and thin layer chromatography (EtOAc / hexanes=¼) indicated that no more starting material was present. The resulting mixture was quenched with saturated NH4Cl solution (5 L), and the o...

example 2

Preparation of Intermediates and Reagents

[0073] Part A: 2-Cyano-N(1,1-dimethylethyl)-2-(hydroxyimino)acetamide 13

[0074] Amide 11 (3.11 g, 22.18 mmol) (Bhawal, B. M.; Khanapure, S. P.; Biehl, E. R.; Syn. Commun., 1990, 20, 3235) dissolved in CH2Cl2 (100 mL) was placed into a 500 mL 3-necked round-bottom flask equipped with a stirring bar. The solution was cooled to 0° C. (ice bath) and NOCl (Fluka) was bubbled through until the reaction mixture turned a brick-red color. The reaction mixture was stirred at 0° C. for 30 min and then at room temperature for 18 hours. The precipitate was collected and washed with CH2Cl2 (25 mL) to afford the product as a white solid (2.88 g, 17.0 mmol).

[0075]1H NMR (400 MHz, DMSO-d6, δ): 7.70 (s, 1H), 3.32 (s, 1H), 1.32 (s, 9H); mp: 218-219° C.

Part B: 2-Amino-2-cyano-N-(1,1-dimethylethyl)acetamide 13

[0076] Oxime 13 (2.5 g, 14.78 mmol), Al amalgam (0.81 g) and distilled H2O (100 mL) were placed into a 250 mL round-bottom flask equipped with a stirr...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

This invention relates to a novel process for the synthesis of Temozolomide, an antitumor compound, and analogs, and to intermediates useful in this novel process.

Description

REFERENCE TO RELATED APPLICATIONS [0001] This application claims priority to U.S. Ser. No. 10 / 050,488 filed on Jan. 16, 2002, which claims the benefit of U.S. Provisional Application Ser. No. 60 / 262,465 filed Jan. 18, 2001.FIELD OF THE INVENTION [0002] This invention relates to a novel process for the synthesis of Temozolomide, an antitumor compound, and analogs, and to intermediates useful in this novel process. BACKGROUND OF THE INVENTION [0003] Temozolomide, 3-methyl-8-aminocarbonyl-imidazo[5,1-d]-1,2,3,5-tetrazin-4(3H)-one, is a known antitumor drug; see for example Stevens et al., J. Med. Chem. 1984, 27,196-201, and Wang et al., J. Chem. Soc., Chem. Commun., 1994, 1687-1688. It has the formula: [0004] It is described in U.S. Pat. No. 5,260,291 (Lunt et al.) together with compounds of broadly similar activity such as higher alkyl analogs at the 3-position. [0005] The synthesis of I by the process described in J. Med. Chem. 1984, 27,196-201 can be simply depicted as follows, eve...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): A61K31/4188A61P35/00C07B51/00C07C255/28C07D233/88C07D233/90C07D487/04
CPCC07C255/28C07D487/04C07D233/90Y02P20/55A61P35/00
Inventor KUO, SHEN-CHUNMAS, JANET L.HOU, DONALD
Owner SCHERING CORP
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap