Adechlorin, a new adenosine deaminase inhibitor containing chlorine production, isolation and properties.

Adechlorin exhibiting a potent inhibitory activity against calf intestinal adenosine deaminase was isolated from the cultured broth of Actinomadura sp. OMR-37. The molecular formula was C11H15N4O4Cl. The aglycone of adechlorin was identical with that of the known adenosine deaminase inhibitors coformycin and 2'-deoxycoformycin. Adechlorin did not exhibit inhibitory activity against various bacteria and fungi at 1.0 mg/ml. The Ki values for adechlorin, coformycin and 2'-deoxycoformycin against adenosine deaminase were determined to be 5.3 X 10(-10) M, 2.1 X 10(-10) M and 7.6 X 10(-11) M, respectively. Adechlorin as well as coformycin and 2'-deoxycoformycin enhanced the antiviral activity of Ara-A. The acute toxicity of adechlorin in mice was less than those of coformycin and 2'-deoxycoformycin.