cAMP(腺苷 3',5'-环状单磷酸酯)和 cAMPS(腺苷 3',5'-环状单硫代磷酸酯)嘌呤支架中 8 位的唑基化提供了具有唑环的衍生物,其通过环状结构直接连接到嘌呤上唑氮。在 8 位进行亲电溴化后,用金属化唑进行亲核取代,得到 8-咪唑和 8-三唑衍生物。底物被适当保护( S p )-3',5'-环状N-苄基氨基磷酸酯。随后的二硫化碳促进了硫代反应,得到了相应的 ( R p )-8-azolo-3'.5'-cAMPS 产物。反应是立体选择性的。产品为三- n-丁基铵盐可溶于有机溶剂并通过色谱法纯化。铵盐转化为钠盐。 图形概要
Cyclic adenosine monophosphate (cAMP) has been converted into its 8-bromo derivative and 2â²O-TBDMS protected before activation of the phosphoric acid moiety with a reagent generated in situ from oxalyl chloride and DMF. Further reactions with primary amines furnished corresponding phosphoramidates with high stereoselectivity at the phosphorus atom. Cross-coupling reactions with the 8-bromopurine yielded 8-hetaryl derivatives. X-Ray analyses showed the amidates to possess the (SP)-configuration. Carbon disulfide effected thiylation under strongly basic conditions stereospecifically provided the (RP)-phosphorothioic acids.