Synthesis of (+)-calanolide A, an anti-HIV agent, Via enzyme-catalyzed resolution of the aldol products
1996; Elsevier BV; Volume: 7; Issue: 11 Linguagem: Inglês
10.1016/0957-4166(96)00433-8
ISSN1362-511X
AutoresAlbert Khilevich, Aye Aye Mar, Michael T. Flavin, John D. Rizzo, Lin Lin, Sergey Dzekhtser, Darko Brankovic, Heping Zhang, Wei Chen, Shuyuan Liao, David E. Zembower, Ze‐Qi Xu,
Tópico(s)Traditional and Medicinal Uses of Annonaceae
ResumoThe synthesis of (+)-calanolide A (1), an anti-HIV-1 agent, is described. A TiCl4-mediated aldol reaction of compound 2 stereoselectively produced the desired syn diastereomer (±)-5, which was resolved by a lipase-catalyzed acylation reaction. Under Mitsunobu conditions (Ph3P/DEAD), the syn aldol product (+)-5 led to the formation of trans-2,3-dimethyl chroman-4-one [(+)-3] with 94% ee, while the anti aldol product (+)-6 yielded both trans and cis derivatives (+)-3 and (+)-4 with 60% and 68% ee, respectively. Luche reduction on (+)-3 led to (+)-1 and (+)-calanolide B in a ratio of 9:1.
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