Synthetic Studies on Phosphorylating Reagent. V. A Convenient Synthesis of 2′,3′-Cyclic Coenzyme A

A convenient method has been developed for the preparation of 2′,3′-cyclic Coenzyme A (5). It was readily prepared in a good yield from the reaction of adenosine-5′ 2-dimethylamino-4-nitrophenyl phosphate (3) with d-pantethine-4′,4″-diphosphate (4) in the presence of acetic acid in pyridine. Compound 3 and the diphosphate 4 were prepared in a good yield from the condensation of adenosine (1) with 2-dimethylamino-4-nitrophenyl phosphate (2) in the presence of dicyclohexylcarbodiimide (DCC) and the phosphorylation of d-pantethine with 2, respectively. Phosphate 5 was hydrolyzed with 0.1 M-hydrochloric acid and subsequently reduced with 2-mercaptoethanol to confirm its structure of 5. One of the products, Coenzyme A (reduced form) (6) showed 102% activity with phosphotransacetylase.