Studies on nucleosides analogs. XVIII. Synthesis of pyrimido-(4,5-c)pyridazine nucleoside analogs.
作者:HARUO OGURA、MASAKAZU SAKAGUCHI、KENKO NAKATA、NOBUKO HIDA、HISAKO TAKEUCHI
DOI:10.1248/cpb.29.629
日期:——
The reactions of 6-hydrazino-1, 3-dimethyluracil (1) with aldoses (2a-e), D-fructose, and D-glucuronolactone gave hydrazones (3a-e, 6, and 8) in good yields, and these products were converted to pyrimido [4, 5-c] pyridazine nucleoside analogs (4a-e, 7, and 9) by cyclodehydration. Stereoisomers were isolated from the reaction mixtures of pyrimido [4, 5-c] pyridazine derivatives, and were examined by CD spectroscopy. On the other hand, the hydrazones (11a, b) of 1 with glycolaldehyde or (±)-glyceraldehyde were converted only to acetates (12a, b). Formation of the pyrimido [4, 5-c]-pyridazine derivatives (13a, b) was not observed.
6-肼基-1,3-二甲基尿嘧啶(1)与醛糖(2a-e)、D-果糖和D-葡萄糖醛内酯的反应以良好产率生成了脎(3a-e,6和8),并通过环化脱水将这些产物转化为嘧啶[4,5-c]并-吡嗪核苷类似物(4a-e,7和9)。从嘧啶[4,5-c]并-吡嗪衍生物的反应混合物中分离出了立体异构体,并通过圆二色谱进行了研究。另一方面,1与乙醇醛或(±)-甘油醛的脎(11a,b)仅转化为乙酸酯(12a,b),未观察到嘧啶[4,5-c]并-吡嗪衍生物(13a,b)的形成。