Biomedical subjects

Yenamandra S Prabhakar

Publications and source records attributed to Yenamandra S Prabhakar.

6 recordsLinked to original sources

PubMed2005

2-(Aryl)-3-furan-2-ylmethyl-thiazolidin-4-ones as selective HIV-RT inhibitors.

A series of 4-thiazolidinones were evaluated as selective inhibitors of the HIV-RT enzyme. Our attempt in correlating the derived physicochemical properties with the HIV-RT inhibitory activity resulted in some statistically significant QSAR models with good predictive ability. The QSAR studies indicated the role of lipophilicity, dipole moment and out-of-plane potential energy of the compounds in rationalizing the activity. One of the compounds, 1, inhibited the enzyme at 0.204 microM concentration with minimal toxicity to MT-4 cells.

Anti-HIV Agents↗

PubMed2005

CP-MLR directed QSAR studies on the antimycobacterial activity of functionalized alkenols--topological descriptors in modeling the activity.

The antimycobacterial activity of nitro/acetamido alkenol derivatives and chloro/amino alkenol derivatives has been analyzed through combinatorial protocol in multiple linear regression (CP-MLR) using different topological descriptors obtained from Dragon software. Among the topological descriptor classes considered in the study, the activity is correlated with simple topological descriptors (TOPO) and more complex 2D autocorrelation descriptors (2DAUTO). In model building the descriptors from other classes, that is, empirical, constitutional, molecular walk counts, modified Burden eigenvalues, and Galvez topological charge indices have made secondary contribution in association with TOPO and/or 2DAUTO classes. The structure-activity correlations obtained with the TOPO descriptors suggest that less branched and saturated structural templates would be better for the activity. For both the series of compounds, in 2DAUTO the activity has been correlated to the descriptors having mass, volume and/or polarizability as weighting component. In these two series of compounds, however, the regression coefficients of the descriptors have opposite arithmetic signs with respect to one another. Outwardly these two series of compounds appear very similar. But in terms of activity they belong to different segments of descriptor-activity profiles. This difference in the activity of these two series of compounds may be mainly due to the spacing difference between the C1 (also C6) substituents and rest of the functional groups in them.

Alcohols↗

PubMed2005

Synthesis and QSAR studies on thiazolidinones as anti-HIV agents.

Selected 4-thiazolidinone have been synthesized and tested as anti-HIV activity. The results of the in vitro tests showed that one of the compounds, 5, inhibited the enzyme at 0.204 microM concentration with minimal toxicity to MT-4 cell. Furthermore, the QSAR studies indicated the role of PMIZ, Ovality and Total energy content of the compounds in rationalizing the activity.

Animals↗

PubMedDate not supplied

A high dimensional QSAR study on the aldose reductase inhibitory activity of some flavones: topological descriptors in modeling the activity.

The quantitative structure-activity relationships (QSAR) of the Aldose Reductase (AR) inhibitory activity of 48 flavones were studied using Free-Wilson, Combinatorial Protocol in Multiple Linear Regression (CP-MLR), and Partial Least Squares (PLS) procedures. For the latter two procedures 152 Molconn-Z parameters and six indicators corresponding to the hydroxyls of flavones were used as molecular descriptors. Independently, all procedures suggested the significance of hydroxyls in modulating the activity of these compounds. The CP-MLR procedure identified 26 descriptors to model the activity. They suggested that structures rich in aromatic CH fragments, with a limited number of aliphatic fragments such as -CH2-, -CH<, and free hydroxyls at 7-, 3'-, and 4'-positions of the 2-arylbenzpyran-4-one core would be preferred for the activity. The PLS analysis agreed with the information content and the relative significance of the descriptors identified in the CP-MLR for modeling the activity. The study offers the scope to modulate the inhibitory activity of these compounds.

Aldehyde Reductase↗

PubMedDate not supplied

A simple algorithm for unique representation of chemical structures-cyclic/acyclic functionalized achiral molecules.

An algorithm, based on "vertex priority values" has been proposed to uniquely sequence and represent connectivity matrices of chemical structures of cyclic/acyclic functionalized achiral hydrocarbons and their derivatives. In this method, "vertex priority values" have been assigned in terms of atomic weights, subgraph lengths, loops, and heteroatom contents. Subsequently, the terminal vertices have been considered upon completing the sequencing of the core vertices. This approach provides a multilayered connectivity graph, which can be put to use in comparing two or more structures or parts thereof for any given purpose. Furthermore, the basic vertex connection tables generated here are useful in the computation of characteristic matrices/topological indices and automorphism groups and in storing, sorting, and retrieving chemical structures from databases.

Journal Article↗

PubMedDate not supplied

Topological descriptors in modeling the antimalarial activity of 4-(3',5'-disubstituted anilino)quinolines.

Two series of closely related antimalarial agents, 7-chloro-4-(3',5'-disubstituted anilino)quinolines, have been analyzed using Combinatorial Protocol in Multiple Linear Regression (CP-MLR) for the structure-activity relations with more than 450 topological descriptors for each set. The study clearly suggested that 3'- and 5'-substituents of the anilino moiety map different domains in the activity space. While one domain favors the compact structural frames having aromatic, heterocyclic ring(s) substituted with closely spaced F, NO(2), and O functional groups, the other prefers structural frames enriched with unsaturation, loops, branches, electronic content, and devoid of carbonyl function. Also, this study gives an indication in favor of the electron rich centers in the aniline substituent groups for better antimalarial activity, an observation in line with several of the previous reports too. The models developed, and the participating descriptors suggest that the substituent groups of the 4-anilino moiety of the 4-(3',5'-disubstituted anilino)quinolines hold scope for further modification in the optimization of the antimalarial activity.

Antimalarials↗