PREPARATION OF NEW DERIVATIVES OF THIAZOLE,THIAZOLIDINE, AND THIAZOL-2-YLPYRAZOLO[3,4-D]PYRIMIDINE SULFONAMIDO CONJUGATES

Several new thiazoles ( 3–7 ), thiazolylpyrazole carbonitrile ( 10 , 11 ), and Thiazolidine sulfonamido conjugate derivatives ( 19–26 ) were prepared starting with p-Piperidinesulfonylacetophenones ( 1 , 2 ). The structure of these compounds was elucidated on the bases of elemental analysis, IR, PMR, and mass spectra. The antimicrobial activities of some selected compounds are also reported.     

Experimental Detection of Induced Damage in Yeast RNA Due to γ‐Irradiation

Non‐isothermal studies by means of thermogravimetric (TG) measurements were carried out using a derivatograph to obtain the number of water molecules per repeat unit of yeast ribonucleic acid (RNA) before and after exposure to γ‐doses of 3 to 600 Gray. IR spectroscopy was utilized to determine which molecular subgroups of RNA adsorb water molecules and to investigate the conformational changes produced in RNA after γ‐irradiation. γ‐Irradiation was found to lead to ring opening or bond cleavage per unit nucleotide, which results in the formation of crosslinked regions (increase in molecular size). Such cleavage becomes more pronounced at doses >300 Gy leading to an increase in the number of water molecules per repeat unit and a decrease in molecular weight (degradation effect). A γ‐dose of 300 Gy may be considered as a critical damaging dose for yeast RNA molecules.