A short synthetic route to the tricyclic guanidinium core of the batzelladine alkaloids
作者:Gregory P. Black、Patrick J. Murphy、Nigel D.A. Walshe
DOI:10.1016/s0040-4020(98)00576-6
日期:1998.8
addition of guanidine to a series of bis-α,β-unsaturated ketones is reported leading to the formation of tricyclic guanidines, which are models of the naturally occurring batzelladinealkaloids. Nmr evidence is given in support of a new assignment for the relative stereochemistry of batzelladine F.
An intramolecular Baylis-Hillman reaction catalysed by secondary amines
作者:Gregory P. Black、Francesca Dinon、Silvia Fratucello、Patrick J. Murphy、Michael Nielsen、Harri Lloyd Williams、Nigel D.A. Walshe
DOI:10.1016/s0040-4039(97)10284-2
日期:1997.12
Treatment of enonealdehydes 4 or 7 with a catalytic amount of a secondary amine lead to the formation of the cyclopentenol 5 or cyclohexenol 8 respectively. Piperidine proved to be the most effective catalyst for this process.
Synthesis of the tricyclic portions of batzelladines A, B and D. Revision of the stereochemistry of batzelladines A and D
作者:Barry B Snider、Jinsheng Chen、Ashok D Patil、Alan J Freyer
DOI:10.1016/0040-4039(96)01575-4
日期:1996.9
The tricyclic portion 4 of batzelladine B (2) is obtained from 10a, which differs in one side chain from the ptilomycalin A model 10c that we prepared several years ago, by reduction with NaBH3CN in buffered MeOH. Hydrogenation of 11b over at 50 PSI H2 affords the proposed tricyclic portion 12b of batzelladine A (1). Epimerization of 12b and hydrolysis affords acid 3, which is similar to, but different
batzelladine B(2)的三环部分4是从10a中获得的,通过在缓冲MeOH中用NaBH 3 CN还原,它的侧链与我们几年前制备的Ptilomycalin A 10c型不同。的氢化11B上,在50 PSIħ 2只得到所提出的三环部分12b的batzelladine A(的1)。12b的差向异构化和水解得到酸3,其类似于但不同于从1的水解获得的酸。五步序列转换7b抗三环酸15,其与1的水解产物相同。通过NOE实验确认了水解产物15的立体化学。