Synthesis of an inhibitor of human immunodeficiency virus infection

Anti-HIV effects of lentinan sulfate were investigated by using an HTLV-I-carrying cell line, MT-4, in vitro. Lentinan, a fungal branched (1----3)-beta-D-glucan, was sulfated to various degrees by means of two kinds of procedures using piperidine N-sulfonic acid in dimethyl sulfoxide or chlorosulfonic acid in pyridine. Lentinan sulfate with a sulfur content of more than 13.9% effectively prevented HIV-induced cytopathic effects (CPE) at concentrations of more than 3.3 micrograms/ml. However, low-substituted lentinan sulfate did not prevent HIV-induced CPE at any concentration tested. When the countercation was 50% Na+ and 50% pyridinium ion, the inhibitory capacity was low. Anticoagulant activity of the lentinan sulfate was also assessed.