Biomedical subjects

M S Babu

Publications and source records attributed to M S Babu.

6 recordsLinked to original sources

PubMed1999

Quantitative structure-activity relationship studies on cyclic cyanoguanidines acting as HIV-1 protease inhibitors.

A quantitative structure-activity relationship study has been performed on some cyclic cyanoguanidines that inhibit the enzyme HIV-1 protease (HIV-1-PR) and exhibit antiviral potency, and the results have been compared with those of cyclic urea derivatives. Both the enzyme inhibition activity and antiviral potency in cyclic cyanoguanidines as well as in cyclic urea derivatives are found to be primarily governed by hydrophobic property of substituents attached to nitrogen (P2/P2') and further enhanced by OH or NH2 group, if any, present in the substituents. However, aromatic substituents are found to be unfavourable to both the activities of cyclic cyanoguanidines but not to any activity of cyclic urea derivatives. Cyclic urea derivatives are indicated to be more potent than cyclic cyanoguanidines. A model for the interaction of cyclic cyanoguanidines with the receptor is proposed.

Cells, Cultured↗

PubMed1999

Quantitative structure-activity relationships of some HIV-protease inhibitors.

A quantitative structure-activity relationship (QSAR) study has been made on different series of cycloalkylpyranones acting as human-immunodeficiency-virus type 1 (HIV-1) protease inhibitors. The results suggest that the enzyme binding affinity of the compounds would be favoured by a cyclooctyl ring, a 3-cyclopropylphenylmethyl substituent at the pyranone ring, and a 4-CN-2-pyridine-, an N-Me-imidazole-, or a 3- or 4-CN-phenyl-sulfonamide group at the meta position of the phenyl ring of the 3-substituent.

Alkanes↗

PubMed1998

A quantitative structure-activity relationship study on some sulfolanes and arylthiomethanes acting as HIV-1 protease inhibitors.

A quantitative structure-activity relationship (QSAR) study on some sulfolanes and arylthiomethanes acting as human immunodeficiency virus-1 (HIV-1) protease inhibitors reveals that in the case of sulfolanes an octahydropyrindene ring and a five-membered 3(S)-sulfolane ring with a hydrophobic 2-substituent (cis to 3-substituent) will be crucial for the inhibition activity. The binding of a sulfolane, which is a nonpeptidic molecule, with the enzyme is shown to partly mimic the binding of a peptidic inhibitor. The 2-substituent is found to have strong hydrophobic interaction with the receptor. Similarly, in the case of arylthiomethanes, one of the substituents of the methane is found to have strong hydrophobic interaction with the enzyme, while the aryl substituent (4-hydroxy-6-phenyl-2-oxo-2H-pyran-3-yl) is assumed to be involved in the hydrogen bondings.

Crystallography, X-Ray↗

PubMed1998

Quantitative structure-activity relationship studies on cyclic urea-based HIV protease inhibitors.

A quantitative structure-activity relationship (QSAR) study is described on some cyclic ureas that inhibit the enzyme HIV-1 protease (HIV-1-PR) and exhibit antiviral potency. Both the enzyme inhibition activity and the antiviral potency were found to be primarily governed by the hydrophobic property of the substituents at the nitrogens (N2/N2') of the urea. Adjacent to the nitrogens, the C1/C1'-substituents are, however, found to affect the activity (inhibition) by their molecular size. The essential binding of the ureas with the receptor is, however, through multiple hydrogen bonding, where the substituents, too, can participate in such binding if they are capable of doing so. A schematic diagram of the overall interaction of the inhibitors with the receptor is presented.

HIV Protease Inhibitors↗

PubMed1982

Genetic studies on the Koya Dora and Konda Kammara tribes of Andhra Pradesh, India.

A total of 209 persons belonging to the Koya Dora and Konda Kammara tribes in the East Godavari District of Andhra Pradesh, have been tested for electrophoretic variation in 9 red cell enzyme systems. The gene frequencies for the systems showing variation are, in general, within the range for other Andhra Pradesh tribal populations. There is 1 example of PHI 2-1 in the Konda Kammara, while 1 case each of PHI 3-1 and 2-1 are reported in the Koya Dora. In PGM1, there is one example of the 6-2 phenotype and one of 4-1 in the Koya Dora. The Koya Dora show a relatively lower frequency of the EsD2 allele compared to the Konda Kammara. The gene frequencies for the GLO system are reported here for the first time among Indian tribals and these are within the Indian range. LDH Calcutta 1 was not detected in either population.

Acid Phosphatase↗

PubMed1982

Blood groups and ABH saliva secretion in Koya Dora and Konda Kammara tribes of Andhra Pradesh.

The present paper reports the distribution of blood groups and ABH saliva secretion in two Andhra tribal populations: the Koya Dora and the Konda Kammara. 100 Koya Dora and nearly 110 Konda Kammara adults of both sexes were tested for A1A2BO, MN, Rh (CcDEe) blood groups and ABH saliva secretion. The gene frequencies for A1A2BO, MN and ABH and the gene as well as chromosome frequencies for Rh (CcDEe) systems were calculated. Koya Doras show a higher incidence of A gene than B gene, while the reverse trend is seen in Konda Kammaras. Both the tribes show a high M gene frequency. No Rh(D) negative individual was found in Koya Doras, while 4.59% of Konda Kammaras are Rh(D) negative. The chromosomes CDE, CdE, cDe, cdE, Cde and cde are absent in Koya Doras, while only the four chromosomes CDE, CdE, cDe and cdE are absent in Konda Kammaras. The chromosome CDe shows the highest frequency in both the tribes. The frequency of secretors is, as usual, higher than that of nonsecretors in both the tribes. The intergroup variation between the two tribes is not statistically significant for MN, Rh (CcDEe) and ABH systems, while the difference is significant for the A1A2BO blood groups. Suitable comparisons have also been made with all the other available data from Andhra Pradesh tribal populations with respect to different systems studied. Finally Fi estimates have been calculated after Harpending et al. (1973) and Workman et al. (1974) for Koya Doras and Konda Kammaras to assess their degree of endogamy, considering the codominant systems studied, which suggest that Koya Doras are relatively more isolated than Konda Kammaras.

ABO Blood-Group System↗