Thioxothienopyrimidinones, alkylthio-and arylalkylthiothienopyrimidinones, thienopyrimidinones, thienopyrimidines a thienopyrimidinedione and a thienotriazolopyrimidinone were prepared from 2-amino-3-carboethoxy-4,5-disubstituted thiophenes and 2-amino-3-cyano-4,5-disubstituted thiophenes via reactions with different reagents.

No abstract

No abstract

The conditions of the reaction of malononitrile dimer with enaminones and arylidenemalononitrile could be adapted to yield either pyridines or benzene derivatives. A new synthesis of pyrido[1,2-a]pyrimidines from the reaction of malononitrile dimer 1 and 2-phenyl-3-piperidin-1-yl-acrylonitrile (11) is described. Compound 1 condensed with DMFDMA to yield an enaminonitrile that reacted with hydrazine hydrate to yield N',4,6-triamino-2H-pyrazolo[3,4-b]pyridine-5-carboxamidine (17).

Treatment of anthranilic acid 1 or 3-amino 2-naphthoic acid 5 with butyl isocyanate in THF led to the formation of the ureido derivatives 3 and 7 respectively, which were cyclized to the corresponding diones 4 and 8 by refluxing in DMF, while the treatment of 1 or 5 with butyl isocyanate in DMF afforded the same diones 4 and 8 respectively. Treatment of 2,4-Bis (trimethylsilyloxy) quinazoline 9 with 1-O-acetyl-2,3,5-tri-O-benzoyl-β-D-ribofuranosyl)quinazoline-2,4(1H-3H)-dione 11. Debenzolation led to the free nucleoside 12. Structural proofs of the prepared compounds are based on spectroscopic methods.

Schiff's bases derived from 2-aminothiazole and substituted benzaldehydes were reacted with [RhCI(PPh3)3] or [Rh-(/~-CI)(COD)] 2 (COD = 1,5-cyclooctadiene) in the presence of four equivalents of PPh3 to give Rh m cyclometallated complexes of the type [RhHCI{ (X-benzylidene) thiazole}-(PPh3)2], in which the imine C H added oxidatively to the metal. The complexes were characterized using i.r., u.v. and n.m.r, spectroscopy. The disposition of the hydride ligand was inferred as trans to a N-donor ligand.

Several heterocyclic compounds containing pyrazole ring are very useful as intermediates for pharmaceuticals 1-4 and have shown several biological activities such as antiinflammatory agents 5-7 , antibacterial 8-12 , antifungal 9 , antiviral 13,14 , antitumor 15-19 and insecticidal 20,21. Numerous pyrazole derivatives are also used in dye industry 22. In our continued interest in the development of highly expedient methods for the synthesis of diverse heterocyclic compounds of biological significance, we report herein the synthesis of some novel pyrazole derivatives which are pyrazolinoquinolizines, 1,4-oxazinopyrazolines, 6-amino-1,4dihydro-pyrano[2,3-c]pyrazole-5-carbonitrile and 4,6dihydropyrazolo[4',3':5,6]pyrano[2,3-d]pyrimidin-5(1H)-one. Moreover, in some cases we used a one pot multicomponents reaction using microwave and ultrasound irradiation. EXPERIMENTAL Melting points were determined using an Electrothermal IA9000 series digital capillary melting point apparatus and are uncorrected. IR spectra were obtained as KBr discs on a 1000-Perkin Elmer FT-IR spectrophotometer. 1 H NMR and 13 C NMR spectra were recorded on a JEOL ECP-300 NMR in CDCl3 (or DMSO-d6) using TMS as an internal standard. Chemical shifts are given in ppm on the δ scale and coupling constants (J) are given in Hz. Electron impact (EI) MS spectra were acquired with the aid of a Shimadzu GCMSQP5050A spectrometer, equipped with a 30 m × 0.25 mm DB-1 glass column, operating with an ionization energy of 70 eV, at the

Five-membered nitrogen heterocycles, especially highly substituted pyrrolidines feature widely in pharmaceuticals, natural alkaloids, organocatalysts and are also useful building blocks in organic synthesis 1. The indole moiety is probably the most well-known heterocyclic compound, a common and important feature of a variety of natural products and medicinal agents 2. Compounds carrying the indole residue, such as isatin (1H-indole-2,3-dione) and its derivatives exhibiting antimicrobial, 3-18 , antiviral 19-23 antiplasmodial 24 antitubercular 25-27 anticancer 28-35 anticonvulsant 36-41 antioxidant 42,43 activities. Due to the above mentioned diverse properties of isatins, we report herein the synthesis of some spirooxoindole compounds using simple, convenient and an efficient one-pot threecomponent reactions. EXPERIMENTAL All commercially available chemicals and reagents were used without further purification. Melting points were acquired in open capillary tubes and were measured on an electro thermal digital melting point apparatus. Infrared data were obtained using Perkin-Elmer, FT-IR spectrometer, as KBr pellets. 1 H, 13 C and the 2D NMR spectra were recorded using a JEOL-NMR spectrometer at 300 MHz and 75 MHz, on solutions in DMSO-d 6 using TMS as an internal standard. Chemical shifts are given in ppm (δ-scale) and the coupling