Enantioselective Syntheses of Monotetrahydrofuran Annonaceous Acetogenins Tonkinecin and Annonacin Starting from Carbohydrates
作者:Tai-Shan Hu、Qian Yu、Yu-Lin Wu、Yikang Wu
DOI:10.1021/jo005643b
日期:2001.2.1
The total synthesis of two mono-THF acetogenins, tonkinecin (1) and annonacin (2), is reported in full detail. Terminal acetylene 3 prepared from D-glucono-delta-lactone and asymmetric dihydroxylation was employed as a common intermediate for both targets 1 and 2. Pd(0)-catalyzed coupling reaction of 3 with vinyl iodides 4 and 5, the chiral centers of which were taken from D-xylose and S-(-)-ethyl
详细报道了两种单-THF产乙酸素,唐宁霉素(1)和番农苷(2)的总合成。由D-葡萄糖酸-δ-内酯和不对称二羟基化反应制得的末端乙炔3被用作靶1和2的通用中间体。Pd(0)催化3与乙烯基碘4和5的偶联反应,其手性中心分别从D-木糖和S-(-)-乙基乳酸中提取,分别得到烯炔26和27。用二酰亚胺对26或27进行选择性氢化,然后除去MOM醚,从而完成了1的合成。在三氟化硼醚化物的存在下,3的锂衍生物与环氧化物6之间的偶联反应得到42。在环氧化物6中获得了两个手性中心来自L-抗坏血酸。随后的催化加氢和MOM保护得到43b。