Table of Contents

Abstract: n/a

Abstract: Treatment of 5-alkyl(aryl)-3H-pyrrolin-2-ones with dichlorocarbene under phase transfer catalysis conditions at 20-30ºC results in a cycloaddition of the carbene to the C=C bond followed by skeletal rearrangement.

Abstract: New substituted thieno[2,3-b]pyridines which contain 4-nitropehnyl and 5-nitro-, carboxy-, methoxycarbonyl-2-furyl groups in the 2 position have been obtained.

Abstract: 3- and 4-monoesterified protocatechuic acid methyl ester (5 and 7 respectively) have been synthesised from quinic acid by a high yields biomimetic rearrangement.

Abstract: Condensation of 1-acetyl-1,2,3,4-tetrahydro-9H-carbazole (2) with some amino compounds furnished the corresponding imino derivatives 3a-e. Compound 3a reacted with chloroacetic acid and underwent cyclization to give the thiazolidine derivative 5. Also, treatment of 3c with thionyl chloride caused cyclization to yield the [1,2,6]thiadiazino derivative 6, which gave the corresponding N-formyl derivative 7 upon heating with ethyl formate. In addition, interaction of 3d with ethyl cyanoacetate yielded the monoamide of malonic acid derivative 8. Acylation of carbazole 1 with succinoyl chloride or phenylacetyl choride produced the corresponding azepine (11) and 1,9-diphenyl acetyl derivatives (14), respectively. Compounds 11, 14 were further reacted to give the carbazole derivatives 12, 13 and 15a,b. The cytotoxic activity for some of the prepared compounds against breast cancer B₂₀ is discussed.

Abstract: The structure of methyl 4-amino-4-cyano-4,6-dideoxy-2,3-O-isopropylidene-α-Ltalopyranoside was established by X-ray analysis confirming a talo configuration at C-4 and suggesting a ¹C₄ conformation of the pyranose ring. The values of relevant torsion angles and calculated puckering parameters revealed a distortion into the direction of ⁵E conformation, thus indicating a flattening at C-2.

Abstract: IR and ¹H-NMR studies on nitrilotriacetic acid (H₃NTA) suggest that the acid exists in the zwitterion form, which allows the existence of intermolecular hydrogen bonding. A tetrahedral structure is established for eleven (1:1) anhydrous acid-metal (II) nitrilotriacetates complexes. The ten Dq values for the colored complexes were determined spectrophotometrically. The pK_a values for the eleven acid metal complexes [M(HNTA)].(OH₂)₃] were determined and compared with the corresponding pK_a values of the [M(OH₂)_n]⁺² ions and also with the log β1 values of the corresponding [M(NTA)]^- complexes. X-ray diffraction studies on the ligand and on eight of these complexes are described.

Abstract: Thermal decomposition of Meldrum's acid derivatives and rearrangement of (alkylsulfanyl) or (propargylamino)methylene ketene intermediates leads in one step to bis thienyl- or bis pyrrolyl-alkanes.

Abstract: The E- and Z- phosphonoalkenyl acyclonucleosides of uracil and thymine were synthesized under Michael addition conditions. Introduction of an alkyl, alkenyl or alkynyl group at the N-3 position of the pyrimidine moiety was accomplished using potassium carbonate in DMF.

Abstract: The present account summarizes the author's studies to elucidate the mechanisms of the recently reported rearrangements resulting from inter- and/or intramolecular reactions of 2-imino-2H-chromene-3-carboxamides with different dinucleophiles.

Abstract: 12H-Benzo[1,3]oxazolo[2,3-b]quinazolin-12-imine (5a), 9-chloro-12Hbenzo[1,3]oxazolo[2,3-b]quinazolin-12-imine (5b), 2,3-dihydro-5H-[1,3]oxazolo[2,3-b]quinazolin-5-imine (5c), 2,3-dihydro-3,3-dimethyl-5H-[1,3]oxazolo[2,3-b]quinazolin-5-imine (5d) and 3,4--dihydro-2H,6H-[1,3]oxazino[2,3-b]quinazolin-6-imine (5e) were synthesized in a one-pot reaction of N-(2-cyanophenyl)chloromethanimidoyl chloride (1) with 2-aminophenols, 2-aminoethanol, and 3-aminopropanol in the presence of a base. The course of the reaction was controlled by the temperature and the amount of base used. N-(2-Cyanophenyl)-(2-hydroxyanilino)methanimidoyl chloride (3a), 2-chloro-3-(2-hydroxyphenyl)-3,4-dihydroquinazolin-4-imine (4a) and 6-imino-2H, 3H, 4H, 6H, 11H-1,3-oxazino[2,3-b]-5-quinazolinium chloride (6) were identified as intermediates of the one-pot process.

Abstract: (1'R)-(+)-3-Hydroxymethyl-1-(1'-phenyl-ethyl)-pyridinium chloride (1), 1-benzyl-3-[1', 3']-dioxolan-2'-yl-pyridinium chloride (2) and (2'S, 4'S, 5'R)-(-)-1-benzyl-3-(3',4'-dimethyl-5'-phenyl-oxazolidin-2'-yl)-pyridinium bromide (3), were transformed by oxidation with potassium ferricyanide into the corresponding 1H-pyridin-2-ones in excellent yields with high regioselectivity.