Abstract:
Two chromone and two diflavone derivatives were designed based on the
results of previous 3D-QSAR and docking studies. All four compounds were
synthesized by one-pot cyclization reaction using DBU as base, and were tested for
their inhibitory activity against HIV-1 protease (HIV-1 PR) by HPLC assay. The
results showed that the inhibitory activity of the synthesized compounds was in the
range of 10-43% inhibition. The 3D-QSAR models were developed for 2-substituted
chromone series against HIV-1 PR using molecular field analysis (MFA) with genetic
partial least squares algorithms (G/PLS). Three different alignment methods; field fit,
pharmacophore-based and receptor-based were used to derive the MFA models. The
receptor-based MFA showed the best statistical results with r2
cv = 0.789, r2 = 0.886
and r2
pred = 0.995. The 3D-descriptors obtained from a receptor-based model can be
mapped very well with the docking simulation study of the most active compound,
32, in this series and can provide guidelines to design more potent HIV-1 protease
inhibitors.
The previously synthesized 2-substituted and 2,3-disubstituted chromone
series, including compounds 1-4 were subjected to docking simulation studies against
wild type and mutant types of HIV-1 PR using GOLD and Autodock3 programs. The
experimental inhibitory activity in terms of log % inhibition were correlated with the
GOLD predicted fitness scores and Autodock docking energies. The correlations
obtained from GOLD gave r2 = 0.4387 and 0.4462 for 2-substituted and 2,3-
disubstituted series, respectively, while Autodock gave r2 = 0.2263 and 0.4552 for 2-
substituted and 2,3-disubstituted series, respectively. The GOLD fitness scores,
Autodock energies and docked conformations supported the high experimental
inhibitory activities of both compounds 32 and 37. Compounds 9 and 42 were
predicted by both GOLD and Autodock as very highly active inhibitors against
various mutant variants. The newly synthesized chromones, compounds 1 and 2, and
biflavone, compound 3 were predicted by GOLD and/or Autodock to possess higher
activity against some mutant types than wild type enzyme. Therefore, chromone
derivatives are promising to serve as potent anti HIV-1 PR drug.