Biotin is prepared by (a) ozonizing methylcyclohexene; (b) reacting nitromethane with the methyl-6-oxohexanoate from a to form 7-nitro-6 hydroxyheptanoic acid methyl ester; (c) acylating to form the corresponding 6 acyloxy compound; (d) forming a double bond at the 6 position; (e) reacting the product of d with nitroethanethiol to form dl-7-thia-6-nitromethyl-9-nitro-nonanoic acid methyl ester; (f) forming a furoxan by cyclization; (g) reducing the furoxan and acylating to form dl-2(4-carbomethoxybutyl)-3,4-bis(acylamido)-2,5-dihydro thiophene; (h) selectively hydrogenating to form the 3,4-cis-bis(acylamido)-2,5-dihydro thiophene; and (i) hydrolyzing and cyclizing to form dl-biotin. The products formed at steps (e)-(h) are novel, as are the individual steps (e), (f), (g), and (h).
生物素的制备方法包括:(a)
臭氧化甲基
环己烯;(b)将
硝基甲烷与由(a)得到的甲基-
6-氧代己酸酯反应,形成7-硝基-6-羟基
庚酸甲酯;(c)酰化,形成相应的6-酰氧化合物;(d)在6位形成双键;(e)将(d)的产物与硝基
乙硫醇反应,形成dl-7-
硫代-6-硝基甲基-9-硝基-
壬酸甲酯;(f)通过环化形成
呋喃并;(g)还原
呋喃并并酰化,形成dl-2(4-羧甲氧基丁基)-3,4-双(酰胺基)-
2,5-二氢噻吩;(h)选择性加氢,形成3,4-顺式-双(酰胺基)-
2,5-二氢噻吩;(i)
水解并环化,形成dl-
生物素。步骤(e)-(h)形成的产物以及步骤(e)、(f)、(g)和(h)本身都是新颖的。