Various interesting heterocycle skeletons were synthesized via Michael type addition reaction with 1,2; 1,3-bidentate nitrogen and carbon nucleophiles. Cycloaddition of different α,β-unsaturated systems afforded bromopyrimidinone 3/5, bromothiazine 4 and bromopyrazole 6a/6b pyrazole-1-carboxylate 8, pyridinylmethanone 9, nicotinonitrile 10, pyrazolopyridine 11a/11b, pyran-3-carbonitrile 12/13, chromenopyridine 14 and N-butyrylpyrazolyl-1-butanone 15 derivatives. The structures of the synthesized compounds were elucidated based on IR, NMR and mass spectral analyses. Group of the newly synthesized compounds were screened for their anti-diabetic activities, whereas compounds 8 and 11b exhibited promising anti-diabetic activities at micro molar concentration against α-glucosidase inhibitor with IC50 values ranging between 13.80-500 μM. On the other hand compound 10 showed a week effect as compared to the standard anti-diabetic agent.

A series of pyrimidine and thiazine derivatives was synthesized by one-pot reaction of cyclopentanone with a mixture of an aromatic aldehyde, namely o-anisaldehyde, and different ureas, namely urea, guanidine and thiourea, respectively. Furthermore, cycloaddition reaction of active methylene reagents, namely acetyl acetone, malononitrile, ethyl cyanoacetate, cyanoacetamide and N-phenyl cyanoacetamide with 2,6-bis(2-methoxybenzylidene)cyclohexanone afforded chromene and quinoline derivatives in basic medium. The antitumor evaluation of some new compounds against three human cell lines, namely MCF-7, NCI-H460 and SF-268 showed significant and moderate activity compared with the positive control doxorubicin.

No abstract

2-Amino benzoic acid was acylated using chloroacetyl chloride followed by cycloaddition with benzylidene derivative to yield pyrimidine 3. Benzoxazone 4 reacted with nucleophilic carbon of phenols 5 and 6, active methylene compounds 11 and 12, and enaminic carbons of 16 and 17 to yield compounds 7, 10, 13, 14, 18 and 19 respectively. Also, benzoxazone 6 reacted with hydrazine to yield compounds 5 and 33. Aminoquinazoline 5 underwent a series of reactions using benzaldhyde, NH 4 SCN in base/acid medium, chloroacetyl chloride and CS 2 followed by cyclization using ethyl chloroacetate to yield compounds 22, 26, 29, 32, 30 and 31 respectively. Hydrazide 33 underwent a series of cycloaddition and cyclocondensation reactions using compounds like ethyl chloroacetate and/or acetyl acetone, maleic anhydride and p-chlorocinnamoyl isothiocyanate to yield compounds 34, 36, 37 and 40 respectively. Finally, compound 6 was reacted with ethyl cyanoacetate and/or acetyl acetone to form compounds 43 and 44 respectively.