Lamivudine

Lamivudine, a synthetic antiretroviral agent, is a dideoxynucleoside reverse transcriptase inhibitor. Lamivudine is the negative enantiomer of a dideoxy analogue of cytidine and is structurally similar to zalcitabine (2',3'-dideoxycytidine, ddC). Lamivudine differs structurally from zalcitabine in that the 3'-carbon of the ribose ring is replaced with sulfur, forming an oxathiolane ring. The absence of a free 3'-hydroxy group on the oxathiolane ring results in the inability of lamivudine to form phosphodiester linkages at this position. Both the positive and negative enantiomers of 2',3'-dideoxy,3'-thiacytidine exhibit antiviral activity in vitro, but lamivudine appears to exhibit greater antiviral activity and to be considerably less cytotoxic than the positive enantiomer. [#]
Source: Aids Info Drugs - Category: Drugs & Pharmacology Source Type: research