73465-36-8

Upstream product

• 120040-62-2 (+)-(2S,3S,4R)-2-(Benzyloxy)-3-<(3,4,5-trimethoxyphenyl)bis(phenylthio)methyl>-4-<3,4-(methylendioxy)benzoyl>tetrahydrofuran 
• 86-81-7 3,4,5-trimethoxy-benzaldehyde 
• 17187-79-0 (E)-4-(benzo[d][1,3]dioxol-5-ylmethyl)-3-(3,4,5-trimethoxybenzylidene)dihydrofuran-2(3H)-one 
• 120040-58-6 Benzo[1,3]dioxol-5-yl-((R)-5-benzyloxy-2,5-dihydro-furan-3-yl)-methanol 
• 120040-59-7 (-)-(2R)-2-(Benzyloxy)-2,5-dihydro-4-<3,4-(methylenedioxy)benzoyl>furan 
• 120040-61-1 5--1,2,3-trimethoxybenzene 
• 104322-41-0 (+)-(2R)-benzyloxy-2,5-dihydrofuran-4-carboxaldehyde 
• 2635-13-4 1,2-(methylenedioxy)-4-bromobenzene 
• 40456-50-6 yatein 
• 17187-77-8 (R)-(+)-3-piperonyl-4-butanolide 
• 147200-54-2 (3S,4S)-3-Hydroxy-4-<3,4-(methylenedioxy)benzyl>tetrahydrofuran 
• 61946-94-9 N-hydroxy-benzo[1,3]dioxole-5-carboximidoyl chloride 
• 73149-51-6 (-)-Dihydroclusin 

Downstream Products

• 127997-59-5 2''-Chloroburseran 

Relevant academic research and scientific papers

Enantiocontrolled Synthesis of Burseran, Brassilignan, Dehydroxycubebin, and Other Tetrahydrofuran Lignans in Both Enantiomeric Forms. Application of Intermolecular Nitrile Oxide Cycloadditions and Lipase Mediated Kinetic Resolutions

Several natural and unnatural tetrahydrofuran lignans have been synthesized by a convergent approach.Our methodology utilizes a nitrile oxide cycloaddition to dihydrofuran 8 and an enzymatic resolution of alcohols 11 by lipase PS.The lipase-mediated kinetic resolution of alcohols 11 furnished both enantiomers of the lignan precursors 12 and 14 in high optical purity (>99percent ee).This is followed by a SN2 displacement of tosylates 15 and 18 by α-lithiobenzyl phenyl sulfides.In this manner, both enantiomers of 3,4-dibenzyltetrahydrofuran (17a, 20a), 3,4-bis(3-methoxybenzyl)tetrahydrofuran (17b, 20b), brassilignan (17c, 20c), dehydroxy cubebin (17d, 20d), and burseran (17e, 20e) were synthesized in overall yields of 6-16percent.

General Conjugate-Addition Method for the Synthesis of Enantiomerically Pure Lignans. Total Synthesis of (-)- and (+)-Burseran, (-)-Dehydroxycubebin, (-)-Trichostin, (-)-Cubebin, (-)-5''-Methoxyhinokinin, and (-)-Hinokinin

Conjugate addition of benzylic diphenyldithioacetal anions to enantiomerically pure (-)-(2R)-and (+)-(2S)-(benzyloxy)-2,5-dihydro-4-furan (2 r and 2 s) gave complete lignan skeletons of the dibenzylbutane class.Desulfurization followed by hydrogenolysis and, when appropriate, oxidation gave the title enantiomerically pure > 99 percent ee) lignans 45 - 50 in 24 - 35 percent overall yields from 2 r and 2 s.