K. F. Suzdalev

Synthesis of Indole 2,3-Epoxypropyl Derivatives and Their Reactions with Amines

Indole derivatives with a 2,3-epoxypropyl substituent attached to nitrogen were synthesized. In reactions with primary and secondary amines these compounds afforded the corresponding 1,2-aminoalcohols.

Chemistry of 1,3-Thiazin-4-ones and Their Derivatives

Publisher Summary 1,3-thiazin-4-ones (TAs) have been the subject of intensive work owing to the uniqueness of their chemistry and the significant biological activity of many of these compounds. Traditionally, the methods of TA syntheses have been classified according to the number of atoms included in the fragments used for the construction of the heterocyclic ring. However, both the availability and structure of the starting materials are undoubtedly important in choosing a synthetic method. The chapter describes each class of TA by starting with the structures of the initial compounds and then illustrates analogous reactions in general schemes. The reactivity of TAs may be considered in two ways. The first consists in describing all the reactions of each separate class of compounds. The second approach is based on the classification into types of reactions of different compounds. The latter approach allows to focus on general and specific peculiarities of transformations and to compare the chemical behavior of various groups of TA derivatives. Progress in the chemistry of 1,3-thiazin-4-ones is mainly attributable to their applications in the pharmaceutical area. In the search for new drugs, the most intensive investigation has focused on the modification of substituents in the thiazinone ring and in the syntheses of thiazinones fused with heterocycles.

Chemistry of 3-acyl-2-haloindoles (Review)

Methods for the synthesis and transformation of 3-acyl-2-haloindoles, which are polyfunctional reagents used for preparing various indole derivatives, are summarized. The reduction and oxidation of the acyl group, condensation at the carbonyl group, nucleophilic and radical substitution of the halogen atom are considered. Reactions leading to [b]-fused indoles are discussed separately.

Synthesis of 1-(oxiran-2-ylmethyl)-1H-indole-3-carbaldehyde and its transformation into amino alcohols containing an indan-1,3-dione fragment

A procedure for the synthesis of 1-(oxiran-2-ylmethyl)-1H-indole-3-carbaldehyde was developed and optimized. Its reaction with indan-1,3-dione, followed by treatment with amines, afforded 1,2-amino alcohols containing an indole fragment.

Cycloaddition of [3]dendralene derivatives to dinitrobenzofuroxan and nitrobenzodifuroxan

Abstract It has been shown experimentally (by NMR spectroscopy and X-ray structural analysis) and theoretically (by quantum-chemical calculations according to DFT with B3LYP/6-31G* basis set) that the cycloaddition of [3]dendralene derivatives to nitrobenzodifuroxan and dinitrobenzofuroxan occurs by a stepwise mechanism with a σ-complex as intermediate. It was shown that the cycloaddition steps occurring contrary to the Alder endo rule are characterized by significant global electrophilicity index differences for the reagents (Δω > 3.0 eV). The stages with Δω ≤ 3.0 eV occurred in accordance with the Alder endo rule as concerted processes. X-ray structural analysis and quantum-chemical calculations within the framework of AIM model identified intramolecular attraction forces between non-bonded atoms in the cycloadduct of phenyldendralene and nitrobenzodifuroxan.

Synthesis and Pharmacological Activity of Amino Alcohols of the Indole Series

Opening of the oxirane ring in 1-oxiranylmethylindoles yielded new indole derivatives containing 1,2-amino alcohol residues at the nitrogen atom. Compounds were studied in vitro in relation to various types of pharmacological activity typical of this class of compounds, including receptor (5-HT2, 5-HT3, P2Y1-ergic, κ-opioid), antiaggregant, hemorheological, antiarrhythmic, and antioxidant activities.

Computer Prognosis and Targeted Synthesis of a New Betulin Derivative Possessing Antituberculous Properties

As is known, the content of betulin in the birch bark,from which this compound can be readily extracted with or-ganic solvents, amounts to 20 – 25%. Betulin was character-ized by a rather restricted spectrum of biological activity[1 – 6]. However, the technological accessibility of betulinand certain structural features of betulin molecules make thiscompound a convenient base for modification. With a viewto searching for chemically accessible substances, we haveperformed a computer screening among 54 betulin deriva-tives which can be obtained in a single-stage synthesis.In order to select the most promising substances, we usedMATRIX – the algorithm of computer prognosis based on ananalysis of descriptors of the three-dimensional structure oforganic molecules [7]. For this analysis, we employed themolecular descriptors (vertical and adiabatic ionization po-tentials, electron affinity, dipole moment, enthalpy ofhydration at 310 K, polarizability and its second derivative,area and volume of a molecule, etc., a total of 149 for eachmolecule) obtained using the readily available and com-monly acceptable programs MOPAC, DRAGON, andGAMESS. The procedure of predicting biological activityconsisted in evaluating the distance between a new moleculeand a basis set selected in the

Synthesis and study of the structure of o-hydroxyaryl-1,2,4-oxadiazoles

The reaction of 4-oxo-1,3-benz- and -naphthoxazinium perchlorates with hydroxylamine leads to 5-(o-hydroxyaryl)-1,2,4-oxadiazoles rather than to 3-(o-hydroxyaryl)-1,2,4-oxadiazoles, as was previously assumed. The structure of the compounds obtained was proved by alternative synthesis, as well as by mass spectrometry and comparison of the experimentally found and calculated dipole moments and Kerr constants of the possible structures of the o-hydroxyaryl-1,2,4-oxadiazoles.

Synthesis and properties of 3-formyl-4H-pyrans

The Vilsmeier formylation of 4H-pyrans afforded 3-formyl-4H-pyrans. These were converted to 3-formylpyrylium salts, from which pyridine or pyridine salts with an aldehyde group at C(3) were obtained. The reaction between 3-formyl-4-allyl-4H-pyran and methyltrifluoromethanesulfonate proceeded via a Koop rearrangement.

Unexpected pyrylium to pyrylium domino transformation. Synthesis of pyrano[3,4-c]pyran-7-ium cation and its recyclization to 2,7-naphthyridine derivative

4-Ethyl-3-formyl-2,6-diphenylpyrylium perchlorate was obtained from 2,6-diphenylpyrylium perchlorate in three steps. Its reaction with triethyl orthoformate was accompanied by rearrangement of the initial pyrylium ring and led to pyrano[3,4-c]pyran-7-ium perchlorate system through a domino process involving ethanol addition-elimination. A plausible mechanism of the reaction is suggested on the basis of DFT quantum-chemical calculations. Reaction of the obtained pyrano[3,4-c]pyran-7-ium perchlorate with ammonium acetate led to a 2,7-naphthyridine derivative without a skeletal rearrangement.