10H-Phenothiazines: a new class of enzyme inhibitors for inflammatory diseases.

The phenothiazine nucleus is known for their inhibitory activity towards the regulatory enzymes that are contributing to diseases such as asthma, autoimmune diseases including allergic rheumatoid and encephalomyelitis. In this study a number of substituted phenothiazines were synthesized and screened for their biological activity against the regulatory enzymes involved in inflammatory diseases. Our results show that the newly synthesized compounds 4a-c and 5a-c exhibited promising target specific enzyme inhibition against phosphodiesterase, prostaglandin dehydrogenase and superoxide dismutase activity depending on steric factors of the molecules.

Two quinazolinones: a ring conformational study.

The molecules of (+/-)-2-(4-methoxyphenyl)-1-phenethyl-2,3-dihydroquinazolin-4(1H)-one, C(23)H(22)N(2)O(2), (I), and (+/-)-2-(1,3-benzodioxol-5-yl)-1-phenethyl-2,3-dihydroquinazolin-4(1H)-one, C(23)H(20)N(2)O(3), (II), have T-shaped forms in the crystal structure. The tetrahydropyrimidine ring in both structures adopts a sofa conformation. Both molecules are linked by N-H.

Dimorphism in (2Z)-2-benzylidene-N,7-dimethyl-3-oxo-5-phenyl-2,3-dihydro-5H-1,3-thiazolo[3,2-a]pyrimidine-6-carboxamide.

The title compound, C22H19N3O2S, crystallizes in two polymorphic forms having the same space group, viz. P-1, with Z' = 2 and Z' = 1. In both polymorphs, the planar thiazole ring is fused cis with the dihydropyrimidine ring, the carbamoyl group is in an extended conformation with an anticlinal orientation with respect to the pyrimidine ring, and the phenyl ring is attached to the pyrimidine ring approximately at a right angle.