the development of multicomponent reactions (mcrs) designed to produce elaborate biologically active compounds has become an important area of research in organic, combinatorial, and medicinal chemistry. a comparative study of the synthesis of new bis-spiro-oxindolo(pyrrolizidines/pyrrolidines) ring systems by the cycloaddition of azomethine ylides generated by a decarboxylative route from sarc...

Both protection and sensitization of Mice C57Bl against 60Co gamma-rays by sulfur-containing amino acid derivatives--S-alkyl-L-cysteines, S-alkyl-2-methyl-DL-cysteines and their hydantoin derivatives, and sulfoxides of these compounds--were examined. DL-5 Allylthiomethyl-5-methylhydantoin (150 mg/kg body weight) had a remarkable radioprotective effect. The survival ratio was 4.3 or above two ti...

To obtain a rapid, efficient and mild synthesis of 5,5-diphenylhydantoin and 5,5-diphenyl-2-thiohydantoin derivatives, ultrasonic irradiation has been applied to the reaction mixtures containing substituted benzils and urea or thiourea derivatives catalyzed by KOH in DMSO/H(2)O, which allowed us to achieve products at room temperature in a good yield and short time without any side product. Thi...

Psammaplin F, an unsymmetrical disulfide bromotyrosine, was isolated from the sponge Pseudoceratina purpurea in 2003. We reported here the first total synthesis of psammaplin F in 12% overall yield by employing Cleland's reagent reduction as key step. The longest linear synthetic sequence starting from 3-bromo-4-hydroxybenzaldehyde and hydantoin was seven steps. In addition, a detailed X-ray cr...

in this paper, new (2e, 2'e)-3, 3'-(((3- hydroxypropane-1, 2-diyl) bis (oxy)) bis (2, 1-phenylene)) bis (1-phenylprop-2-en-1-one) (2a) was prepared in good yield by condensation reaction of acetophenone with bisaldehyde (1a) in ethanolic naoh solutions at room temperature. the (2e, 2'e)-3, 3'-(((3- hydroxypropane-1, 2-diyl) bis (oxy)) bis (2, 1-phenylene)) bis (1-phenylprop-...

The methylation and oxidative demethylation of cytosine in CpG dinucleotides plays a critical role in the regulation of genes during cell differentiation, embryogenesis and carcinogenesis. Despite its low abundance, 5-methylcytosine (5mC) is a hotspot for mutations in mammalian cells. Here, we measured five oxidation products of 5mC together with the analogous products of cytosine and thymine i...