Practical Synthesis of an Enantiomerically Pure trans-4,5-Disubstituted 2-Pyrrolidinone via Enzymatic Resolution. Preparation of the LTB4 Inhibitor BIRZ-227
摘要:
A practical synthesis of the enantiomerically pure BIRZ-227 (1), a,LTB4 inhibitor, has been developed. The key steps include the effective synthesis of the trans-diarylpyrrolidinone (+/-)-8 and the enzymatic resolution of N-acetoxymethyl pyrrolidinone (+/-)-10 by immobilized Lipase Novozym 435. Reduction of pyrrolidinone (+)-8 with borane and subsequent coupling with chlorobenzoxazole 2 furnished BIRZ-227 in high enantiomeric purity (99% ee). The overall process described herein required no chromatographic separation and is amenable to the preparation of multikilogram quantities of the desired drug candidate in a cost-effective manner.
Practical Synthesis of an Enantiomerically Pure trans-4,5-Disubstituted 2-Pyrrolidinone via Enzymatic Resolution. Preparation of the LTB4 Inhibitor BIRZ-227
摘要:
A practical synthesis of the enantiomerically pure BIRZ-227 (1), a,LTB4 inhibitor, has been developed. The key steps include the effective synthesis of the trans-diarylpyrrolidinone (+/-)-8 and the enzymatic resolution of N-acetoxymethyl pyrrolidinone (+/-)-10 by immobilized Lipase Novozym 435. Reduction of pyrrolidinone (+)-8 with borane and subsequent coupling with chlorobenzoxazole 2 furnished BIRZ-227 in high enantiomeric purity (99% ee). The overall process described herein required no chromatographic separation and is amenable to the preparation of multikilogram quantities of the desired drug candidate in a cost-effective manner.
This invention relates to a transition metal mediated process for the preparation of optionally substituted 2-amino-benzoxazoles and or 2-amino-benzimidazoles, which are useful as therapeutic agents or as intermediates in the synthesis of therapeutic agents.
A practical one-pot synthesis of trans-4,5-disubstituted 2-pyrrolidinones and the related pyrrolidines
作者:Nathan K. Yee
DOI:10.1016/s0040-4039(97)01134-9
日期:1997.7
A practical and general method for the stereoselective synthesis of trans-4,5-disubstituted 2-pyrrolidinones was developed. Hydride reduction of these pyrrolidinones gave the corresponding pyrrolidines. (C) 1997 Elsevier Science Ltd.
Resolution and assignment of the absolute stereochemistry of a trans-2,3-diarylpyrrolidine LTB4 inhibitor intermediate
作者:Gregory P Roth、Michel Emmanuel、Liang Tong
DOI:10.1016/s0957-4166(96)00512-5
日期:1997.1
1,3-Cycloaddition of an azaallyl anion with 4-methoxystyrene furnishes the corresponding racemic trans-pyrrolidine. Resolution of both enantiomers was accomplished by fractional crystallization with the inexpensive diacetone-2-keto-L-gulonic acid. The absolute stereochemistry was determined by single crystal X-ray analysis of the corresponding sulfonamide. (C) 1997 Elsevier Science Ltd.
Practical Synthesis of an Enantiomerically Pure <i>trans-</i>4,5-Disubstituted 2-Pyrrolidinone via Enzymatic Resolution. Preparation of the LTB<sub>4</sub> Inhibitor BIRZ-227
作者:Nathan K. Yee、Laurence J. Nummy、Denis P. Byrne、Lana L. Smith、Gregory P. Roth
DOI:10.1021/jo971605p
日期:1998.1.1
A practical synthesis of the enantiomerically pure BIRZ-227 (1), a,LTB4 inhibitor, has been developed. The key steps include the effective synthesis of the trans-diarylpyrrolidinone (+/-)-8 and the enzymatic resolution of N-acetoxymethyl pyrrolidinone (+/-)-10 by immobilized Lipase Novozym 435. Reduction of pyrrolidinone (+)-8 with borane and subsequent coupling with chlorobenzoxazole 2 furnished BIRZ-227 in high enantiomeric purity (99% ee). The overall process described herein required no chromatographic separation and is amenable to the preparation of multikilogram quantities of the desired drug candidate in a cost-effective manner.