O. V. Gulyakevich

3-acetyl-4-methylpyrido[2,1-a]-isoquinolin-2-ones. [2+4] cyclocondensation of 3,4-dihydroisoquinolines with triacetylmethane

Treatment of 3,4-dihydroisoquinolines with triacetylmethane in refluxing alcohol for 2-3 h gave 3-acetyl-4-methylpyrido[2,1-a]isoquinolin-2-ones. Their basic physicochemical properties have been studied.

ANGULARLY ALKYLATED 8-AZA-D-HOMOGONANES

We have established that cyclic azomethines (1-alkyl-substituted 3,4-dihydroisoquinolines) enter into the annelation reaction with cyclic β-triketones (2-acyl-1,3-cyclohexanediones) with formation of C-9 angularly alkylated 8-aza-D-homogonanes. We have shown that the reaction of asymmetric β-triketones (2-acetyl-5,5-dimethyl-4-methoxycarbonyl-1,3-cyclohexanedione) is accomplished regioselectively, leading to the 17-methoxycarbonylated 8-aza-D-homogonane derivative, existing in solutions in the form of a mixture of stereiosomers with respect to C-17 (due to keto-enol tautomerism) and in crystals in the form of a single stereoisomer. The structure of the 8-azo-D-homogonanes has been proven by UV, IR, and PMR spectra.

Regioisomeric acetoxy derivatives of 8-aza-D-homogona-12,17a-dione. Annelation of 1-methyl-3,4-dihydroisoquinoline with 4-acetoxy-2-acetylcyclohexane-1,3-dione

Annelation ([2+4] cyclocondensation) of 1-methyl-3,4-dihydroisoquinoline with 4-acetoxy-2-acetyl-cyclohexane-1,2-dione leads to a mixture of regioisomeric acetoxy derivatives of 9-methyl-8-aza-D-homogona-12,17a-dione.

Interaction of Cyclic Schiff's Bases with 2-Methylthiopyrimidine-4,6-dione Enol Acetate. Synthesis of 5-(2-Acetyl-6,7-dimethoxy-1,2,3,4-tetrahydro-1-isoquinolyl)-6-hydroxy-2-methylthio-1,4-dihydro-4-pyrimidinones

Abstract5-(2-Acetyl-1,2,3,4-tetrahydro-1-isoquinolyl)-6-hydroxy-2-methylthio-1,4-dihydro-4-pyrimidinones have been obtained by the interaction of 3,4-dihydroisoquinolines with 2-methylthio-4-oxo-1,4-dihydro-6-pyrimidinyl acetate. It was shown that N,O-methyl derivatives are formed in interaction of the obtained products with diazomethane.

[3 + 3] Cyclocondensation of 1-alkyl-3,4-dihydroisoquinolines with β-keto esters. New annelation reaction in a series of cyclic Schiff’s bases

A new annelation reaction in a series of cyclic Schiff’s bases is described with examples of [3 + 3] cyclocondensation of 1-alkyl-3,4-dihydroquinolines and acetoacetic esters.

Investigation of the regio-and stereoselectivity of the annelation reaction of cyclic schiff base with structurally asymmetrical β,β′-triketones. Synthesis and properties of 17-acetoxy-8-aza-D-homogona-12,17a-diones

Annelation ([2+4]-cyclocondensation) of 3,4-dihydroisoquinolines and 2-acetyl-4-acetoxycyclohexane-1,3-dione gives 17-acetoxy-8-aza-D-homogona-12,17a-diones as a mixture of the C(9),C(17)-stereoisomers with the (9R,17S: 9S,17R) racemic pair predominating.

17a-acetoxy-16,16-dimethyl-8-aza-D-homogona-1,3,5(10),9(11),13,17-hexaen-12-one, the product of acylotropic rearrangement at interaction of 16,16-dimethyl-8-aza-D-homogona-1,3,5(10),9(11),13-pentaene-12,17a-dione with acetic anthydride

On interaction of 16,16-dimethyl-8-aza-D-homogona-1,3,5(10),9(11),13-pentaene-12, 17a-dione with acetic anhydride acylotropic rearrangement occurs with the formation of a single product, viz. 17a-acetoxy-16, 16-dimethyl-8-aza-D-homogona-1,3,5(10),9(11),-13, 17a-hexaen-12-one. The effect of sodium acetate and of acetic acid concentration on the result of the reaction has been studied. The structure of the product was confirmed by data of elemental analysis, IR, UV,1H, and13C NMR spectroscopy, mass spectrometry, and also X-ray structural analysis.

Synthesis of 17a-ethoximino derivatives of 8-aza-d-homogona-12,17a-diones by annelation of 3,4-dihydroisoquinolines with 2-acetyl-3-ethoximino-5,5-dimethylcyclohexanone

Abstract[2+4] Cyclocondensation of 3,4-dihydroisoquinolines with 2-acetyl-5,5-dimethyl-3-ethoximinocyclo-hexanone has been used to synthesize the previously unavailable 17a-ethoximino derivatives of 8-aza-D-homogona-12,17a-diones.

[3+3]-Cyclocondensation of aminomethylenecycloalkanones with cyclic azomethines — A new approach to condensed nitrogen heterocycles

A new method was developed for the synthesis of condensed azinium salts with a nitrogen atom in the ring fusion based on the [3+3]-cyclocondensation of aminomethylenecycloalkanones and cyclic azomethines.

Interaction of 8-AZA-D-homogona-1,3,5(10),13-tetraene-12,17a-diones with acetic anhydride — New directions in the transformation of conformationally restrictedα-acyl-β-aminovinyl ketones

The interaction of 16,16-dimethyl-8-aza-D-homogona-1,3,5(10),13-tetraene-12,17a-diones with acetic anhydride has been investigated. In the presence of fused sodium acetate, the major products are 11-vinyl-16,16-dimethyl-8-aza-D-homogona-1,3,5(10),9(11),13-pentaene-12,17a-dione; minor products are 16,16-dimethyl-8-aza-D-homogona-1,3,5(10),9(11),13,17-hexaen-12-ones. In the absence of sodium acetate, the reaction stops at the 11-acetyl-16,16-dimethyl-8-aza-D-homogona-1,3,5(10),13-tetraene-12,17a-dione derivative. In the case of 2,3-demethyoxy-8-aza-D-homogonane, a different principal product is formed, regardless of whether or not sodium acetate is present; this is a compound that results from the formation of a bond between the orignal homogonane and 8-aza-D-homogona-1,3,5(10),9(10),13,17-hexaen-12-one (which is formed during the course of the reaction) at positions 9 and 4, respectively. The structure of the compounds that were obtained has been verified by a set of physicochemical data (IR and UV spectra, PMR, and x-ray diffraction). A probable scheme is proposed for the basic directions of the reaction.