Bracher F
Institut für Pharmazeutische Chemie, Technischen Universität, Braunschweig.
Arch Pharm (Weinheim). 1994 Jun;327(6):371-5. doi: 10.1002/ardp.19943270605.
Two strategies towards the synthesis of isomerically pure azafluorenones are described. Cyclization of the aryl nicotinic acid 7 with polyphosphoric acid and subsequent reductive debromination gives 8-methoxyonychine (3) ("method A"). 6-Methoxyonychine (2), an alkaloid from annonaceae, can be prepared by Parham-cyclization of the carboxylic acid 7 or of the ester 6 ("method B"). In an agar-well diffusion assay 2, 3, and onychine (9a) show moderate activity against Candida albicans. 9e has stronger activity, while other azafluorenones are almost inactive. The structurally related azaoxoaporphine alkaloid sampangine (12) has very strong antifungal activity.
描述了两种合成异构体纯氮杂芴酮的策略。芳基烟酸7与多磷酸环化，随后进行还原脱溴得到8-甲氧基奥尼辛（3）（“方法A”）。6-甲氧基奥尼辛（2），一种来自番荔枝科的生物碱，可以通过羧酸7或酯6的帕尔哈姆环化反应制备（“方法B”）。在琼脂孔扩散试验中，2、3和奥尼辛（9a）对白色念珠菌显示出中等活性。9e具有更强的活性，而其他氮杂芴酮几乎没有活性。结构相关的氮杂氧杂阿朴啡生物碱桑潘金（12）具有非常强的抗真菌活性。
