83889-77-4Relevant academic research and scientific papers
Chiral squaramide-mediated methanolytic desymmetrization of prochiral cyclic anhydride: A convenient approach for synthesizing roche lactone
Ding, Liang-Qian,Hong, Dan-Feng,Liu, Wen-Guang,Ma, Hui,Tan, Qing-Gang,Wang, Shi-Heng,Wu, Si-Qin,Xiong, Fei
, p. 429 - 432 (2018/09/25)
The main objective of this report was to develop an improved process for the asymmetric synthesis of (3aS, 6aR)-lactone 1, which is the key chiral intermediate of (+)-biotin. This practical and efficient process includes a novel chiral squaramide alkamine derivatives 5 mediated methanolytic desymmetrization of prochiral cyclic anhydride 3 to produce the enantiomerically enriched precursor of Roche lactone.
A family of novel bifunctional organocatalysts: Highly enantioselective alcoholysis of meso cyclic anhydrides and its application for synthesis of the key intermediate of P2X7 receptor antagonists
Yang, Hong-Jun,Xiong, Fang-Jun,Li, Jie,Chen, Fen-Er
, p. 553 - 558 (2013/07/27)
A family of novel squaramides/sulfamides based on 1,2-alkamine was developed as chiral bifunctional catalysts to promote the asymmetric alcoholysis of meso cyclic anhydrides. The hemiesters were obtained in high yield with up to 93% ee. The usefulness of this methodology was demonstrated in the asymmetric synthesis of the key intermediate of P2X7 receptor antagonists.
Highly enantioselective methanolysis of meso-cyclic anhydride mediated by bifunctional thiourea cinchona alkaloid derivatives: Access to asymmetric total synthesis of (+)-biotin
Xiong, Fei,Xiong, Fang-Jun,Chen, Wen-Xue,Jia, Hui-Qing,Chen, Fen-Er
, p. 1078 - 1082 (2013/10/21)
An enantioselective asymmetric total synthesis of (+)-biotin (1) via the Hoffmann-Roche lactone-thiolactone strategy has been accomplished from commercially available cis-1,3-dibenzyl-2-imidazolidone-4,5-dicarboxylic acid (2). Strategic transformations include a cinchona alkaloid-based bifunctional thiourea mediated methanolytic desymmetrization of prochiral cyclic anhydride 3 to produce the enantiomerically enriched precursor of Roche lactone 5 and an improved introduction of the 4-carboxybutyl side chain at C-4 position of Roche thiolactone 6 via Grignard reaction.
Synthetic studies on (+)-biotin, part 151: A chiral squaramide-mediated enantioselective alcoholysis approach toward the total synthesis of (+)-biotin
Chen, Xu-Xiang,Xiong, Fei,Fu, Han,Liu, Zhi-Qian,Chen, Fen-Er
, p. 488 - 491 (2011/05/14)
An efficient stereocontrolled total synthesis of (+)-biotin (1) has been achieved via the intermediacy of Roche's lactone 5 starting from cis-1,3-dibenzyl-2-imidazole-4,5-dicarboxylic acid (2). The bifunctional cinchona alkaloid-derived squaramide-promoted enantioselective alcoholysis was utilizing as a tool for the construction of two contiguous stereocenters of C-3a and C-6a in biotin molecular with excellent enantioselectivity. In addition, the 4-carboxybutyl side chain was assembled by first using C4+C1 approach via a novel tricyclic thiophanium salt intermediate.
An improved asymmetric total synthesis of (+)-biotin via the enantioselective desymmetrization of a meso-cyclic anhydride mediated by cinchona alkaloid-based sulfonamide
Xiong, Fei,Chen, Xu-Xiang,Chen, Fen-Er
experimental part, p. 665 - 669 (2010/07/17)
The highly enantioselective total synthesis of (+)-biotin 1 via the Hoffmann-Roche lactone-thiolactone strategy has been achieved starting from cis-1,3-dibenzyl-2-imidazolidone-4,5-dicarboxylic acid 2 with an overall yield of 35%. Two contiguous stereogenic centers at C-3a and C-6a were established through a rapid cinchona alkaloid-based sulfonamide-mediated enantioselective alcoholysis of meso-cyclic anhydride 3 to afford (4S,5R)-cinnamyl hemiester 4h, the direct precursor to (3aS,6aR)-lactone 5 with high enantioselectivity. A one-pot installation of the 4-carboxybutyl side chain was accomplished by a Fukuyama coupling reaction of (3aS,6aR)-thiolactone 6 with the organozinc reagent prepared from ethyl 5-bromopentanoate.
Total synthesis of (+)-biotin via a quinine-mediated asymmetric alcoholysis of meso-cyclic anhydride strategy
Huang, Jian,Xiong, Fei,Chen, Fen-Er
, p. 1435 - 1442 (2008/12/20)
A concise asymmetric total synthesis of (+)-biotin 1 has been accomplished in which the absolute stereochemistry of C3a, C6a of 1 was established by utilizing an efficient and practical quinine-mediated asymmetric alcoholysis of meso-cyclic anhydride 2 in a single step, the C4 stereochemistry was installed by a direct stereoselective ionic hydrogenation of the thiolactol 7.
Synthetic studies on d-biotin, part 8: An efficient chemoenzymatic approach to the asymmetric total synthesis of d-biotin via a polymer-supported PLE-mediated desymmetrization of meso-symmetic dicarboxylic esters
Chen, Fen-Er,Chen, Xu-Xiang,Dai, Hui-Fang,Kuang, Yun-Yan,Xie, Bin,Zhao, Jian-Feng
, p. 549 - 554 (2007/10/03)
A practical chemoenzymatic method for the asymmetric total synthesis of d-biotin (1) starting from the commercially available cis-1,3-dibenzyl-2- imidazolidone-4,5-dicarboxylic acid (2) has been developed. The key step of the synthesis is the highly enantioselective hydrolysis of meso-dicarboxylic esters by a polymer-supported pig liver esterase and introduction of a formyl group at the C-4 position in 4 via a Grignard reaction. The polymer-supported PLE can be recovered quantitatively from the reaction mixture by simple filtration and reused without significant loss of activity.
Process for producing optically active hemiesters
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, (2008/06/13)
There is disclosed a process for producing an optically active hemiester of formula (1): 1wherein R1, R2 and R5 represent the same meanings as described below, which comprises reacting a cyclic acid anhydride of formula (2): 2wherein R1 and R2 are different and independently represent a hydrogen atom, a halogen atom, an alkyl group optionally substituted with an alkoxy group or a halogen atom, and the like, with a hydroxy compound of formula (3): R3OH ??(3) wherein R3 represents an alkyl group optionally substituted with an alkoxy group, a phenoxy group, a dialkylamino group or a halogen atom and the like, in the presence of an asymmetric catalyst.
A formal catalytic asymmetric synthesis of (+)-biotin with modified cinchona alkaloids
Choi,Tian,Deng
, p. 1737 - 1741 (2007/10/03)
A formal catalytic asymmetric synthesis of (+)-biotin was realized. The key steps involve a catalytic, highly enantioselective and quantitative desymmetrization of a meso cyclic anhydride followed by a one-pot chemoselective reduction to form the optically active lactone intermediate in the Goldberg - Sternbach (+)-biotin synthesis.
Intermediates to optically active cis-1,3-dibenzyl-hexahydro-1H-furo[3,4-d]imidazole-2,4-dione
-
, (2008/06/13)
A process for preparing an optically active cis-1,3-dibenzylhexahydro-1H-furo[3,4-d]imidazole-2,4-dione of the formula: STR1 wherein an asterisk (*) indicates an asymmetric carbon, Bzl represents a benzyl group and the 3a- and 6a-positions take the cis-configuration, which comprises reducing selectively an optically active cis-imidazolidinedicarboxylic acid monoester of the formula: STR2 wherein R is a C1 -C6 alkyl group and Bzl is as defined above with a reducing agent at either one of the carboxyl group and the alkoxycarbonyl group in the said monoester, followed by cyclization, the said monoester being the one obtainable by hydrolysis of a cis-imidazolidinedicarboxylic acid diester of the formula: STR3 wherein R and Bzl are each as defined above with an enzymatic material having a capability of hydrolyzing the ester group in the said diester.
