Synthesis of Pyrrolidine Analogues ofN-Acetylneuraminic Acid as Potential Sialidase Inhibitors
作者:L�szl� Czollner、J�nos Kuszmann、Andrea Vasella
DOI:10.1002/hlca.19900730522
日期:1990.8.8
The pyrrolidine derivatives 3, 4, and 5 were prepared from the methyl ester 7 of Neu2en5Ac via lie pyrrolidine-borane adduct 33. They inhibit Vibrio cholerae sialidase competitively with Ki = 4. 4 10−3 M, 5. 3 10−3 M, and 4. 0 10−2 M, respectively. Benzylation of 7 gave the fully O-benzylated 8 besides 9, 10, and 11. Ozonolysis and reduction with NaBH4 of 8 and 9 gave the 1, 4-diols 12 and 15, the
的吡咯烷衍生物3,4和5是从甲基酯制备7 Neu2en5Ac的经由谎言吡咯烷甲硼烷加成物33。它们分别以K i分别为4. 4 10 -3 M,5。3 10 -3 M和4. 0 10 -2 M抑制霍乱弧菌唾液酸酶。的苄基化7得到充分ø -benzylated 8除了9,10,和11臭氧分解和还原用NaBH 4的8和9分别得到1,4-二醇12和15,乙酸羟基酯13和16以及呋喃糖酶14和17(方案1)。二醇12被选择性保护(19 20 23),并通过Mitsunobu反应转化为叠氮化物27。容易的乙酰基迁移阻碍了由12获得的双乙酸酯22的选择性碱催化的脱保护。甲磺酸盐28被证明是不稳定的。叠氮化物27转化通过将29引入酮30中(方案2)。氢化30得到二氢吡咯31,因此得到吡咯32。加合物33通过施陶丁格反应(31)并用LiBH 4 / HBF 4还原而从30获得。它被转化为吡咯烷34。通过X射