Solution- and solid-phase synthesis and anti-HIV activity of maslinic acid derivatives containing amino acids and peptides.

Maslinic acid (1) has been coupled at C-28 with several alpha- and omega-amino acids by using solution- and solid-phase synthetic procedures. Twelve derivatives (2-13) with a single amino acid residue were prepared in solution phase, whereas a dipeptide (14), a tripeptide (15), and a series of conjugate dipeptides (16-24) were synthesized in solid phase. The anti-HIV activity of these compounds was assessed on MT-2 cells infected with viral clones carrying the luciferase gene as a reporter. While in maslinic acid (1) were present both cytotoxic and antiviral activities, only the derivatives 13 and 24 showed anti-HIV-1 activity and therefore represent a novel class of anti-HIV-1 compounds.