The 7-N-Oxides of Purines Related to Nucleic Acids: Their Chemistry, Synthesis, and Biological Evaluation
摘要:
Recent advances in the chemistry, synthesis, and biological evaluation of the 7-N-oxides of purines related to nucleic acids are reviewed. The 7-N-oxides covered are those of guanine (1), adenine (2), and hypoxanthine (3) and of related compounds such as 6-mercaptopurine (6-MP) (72), the 6-thioxo analogue of 3, and 6-methylthiopurine, a simple model for azathioprine (78), which were all unknown until recently.
The first synthesis of the antitumorantibiotic guanine 7-oxide (VI) has been achieved via a 4-step route starting from phenacyl bromide (I) and the nitropyrimidone III and proceeding through the intermediates IVe and Ve.
A purified isolate of an actinomycete identified as ATCC 39364 is capable of producing the antimicrobial/antitumor compound 2-amino-1,9-dihydro-6H-purine-6-one-7-oxide, commonly known as guanine-N.sup.7 -oxide. Guanine-N.sup.7 -oxide is produced by cultivating isolate ATCC 39364 under aerobic conditions in a culture medium containing assimilable sources of carbon and nitrogen until a substantial amount of the compound is produced and thereafter isolating the compound. The antibiotic/antitumor compound guanine-N.sup.7 -oxide and pharmaceutical compositions comprising this compound or one of its pharmaceutically acceptable salts together with a pharmaceutically acceptable carrier are also disclosed as is a method of treating microbial infections in a mammal or of treating tumors in a mammal.
A full account is given of the first chemical synthesis of the antitumor antibiotic guanine 7-oxide (5) and its9-substitutedderivatives (24a--k and 26). Coupling of appropriate primary amines (17a--e, g--k) with phenacyl bromide (16) produced, after treatment with HCl, the corresponding N-substituted phenacylamine hydrochlorides (18a--e, g--k). A similar phenacylation of 4-amino-l-butanol (21) failed
全面介绍了抗肿瘤抗生素鸟嘌呤7-氧化物(5)及其9-取代衍生物(24a-k和26)的首次化学合成。用HCl处理后,将适当的伯胺(17a-e,g-k)与苯甲酰溴(16)偶联,制得相应的N-取代的苯甲胺盐酸盐(18a-e,g-k)。4-氨基-1-丁醇(21)的类似苯甲酰化反应未能得到所需的化合物18f,因此将其与2-溴甲基-2-苯基-1,3-二氧戊环(20)在150-155摄氏度下加热在用HCl处理3小时后,提供氨基缩酮盐酸盐22,产率为40%。用热的2 N HCl水溶液对22进行缩酮化处理,得到18f,产率为96%。由盐酸盐18a-1和1N NaOH水溶液原位生成的游离碱的缩合,用氯嘧啶酮6在沸点EtOH水溶液中于沸点下进行20分钟或在25-30℃下进行3-24h,以54-90%的产率得到6-苯甲氨基-4-嘧啶酮19a-1。在室温下用2N NaOH水溶液处理10-60分钟后,硝基嘧啶酮19a