Untitled

Britsun, V. N.; Esipenko, A. N.; Lozinskii, M. O.

doi:10.1023/a:1019906411570

Cited by 8 publications

(8 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Methods have also been developed for the synthesis of 2-aryl-2,3,6,7,8-pentahydro-4H-pyrimido[2,1-b]-1,3-thiazin-4-ones 95 [79] and 7-acetyl-2,8-diaryl-9-cyano-6-methyl-3,4-dihydro-2H,8H-pyrido[2,1-b]-[1,3]thiazin-4-ones 94 [80], involving the reaction of 1H-3,4,5,6-tetrahydropyrimidine-2-thione and 5-acetyl-3-cyano-6-methyl-4-phenyl-1,4-dihydropyrimidine-2(3H)-thione with 3-aryl-2-propenoyl chlorides 89 in pyridine. [81,82].…”

Section: Reactions With 3-aryl-2-propenoyl Chloridesmentioning

confidence: 99%

Cycloacylation of thioamides and their derivatives by compounds containing an activated multiple bond (review)

Britsun

Lozinskii

2007

Chem Heterocycl Comp

Self Cite

View full text Add to dashboard Cite

The cycloacylation reactions of thioamides and their derivatives containing an activated multiple bond are analyzed and summarized.The cycloacylation of thioamides and their derivatives containing an activated multiple bond is an accessible and convenient method for the synthesis of five-and six-membered sulfur-and nitrogen-containing heterocycles -primarily 4H-1,3-thiazin-4-ones [1] and thiazolidin-4-ones [2], and also 2-thioxopiperidines [3], thiopyran-4-ones [4], and pyrimidin-4-ones [5]. Heterocyclic compounds of these types exhibit a wide spectrum of biological activity and have extensive practical applications [1,2,6].This group of reactions is also of interest from the theoretical standpoint since they make it possible to study, analyze, and predict the relationships between the reactivity of substrates containing the ambident NH─C═S group and their structure, reaction conditions, and the nature of substituents at the heteroatoms. Therefore, in spite of the fact that the first papers on this subject were published 50 of more years ago [7,8] synthetic investigations in the field are continuing to this day [9][10][11][12].Nevertheless, no reviews have been published on this subject. It should be mentioned that certain methods for the cycloacylation of thioamides by derivatives of unsaturated carboxylic acids were analyzed in reviews on the synthesis of 1,3-thiazines [1] and thiazolidin-4-ones [2, 13], reactions of N-aminoazolinethiones and N-aminoazinethiones [14], thioamides [15][16][17], and carbon suboxide [18]. However, the information on this subject in these publications has not been coordinated and is not exhaustive.New publications on the cycloacylation of thioamides, in which the range of both reagents and substrates has been extended, have appeared recently. Modern physical methods of establishing the structure of the synthesized products were used, and this made it possible to prove their structure unequivocally.For this reason we attempted to fill the gap and to analyze the information concerning the cycloacylation of acyclic and cyclic thioamides by compounds containing an activated multiple bond. This reviews covers papers not examined in [1,2,[13][14][15][16][17][18] and also papers that have appeared more recently.

show abstract

Section: Reactions With 3-aryl-2-propenoyl Chloridesmentioning

confidence: 99%

Cycloacylation of thioamides and their derivatives by compounds containing an activated multiple bond (review)

Britsun

Lozinskii

2007

Chem Heterocycl Comp

Self Cite

View full text Add to dashboard Cite

show abstract

“…We earlier developed a general approach to synthesis of 2-aryl-2,3-dihydro-4H-[1,3]thiazino[3,2-a]benzimidazol-4-ones, based on cyclization of benzimidazole-2-thione with 3-arylacryloyl chlorides [2,3]. We thought it would be interesting to study and compare the chemical properties of 2,3-dihydro-4H-[1,3]thiazino[3,2-a]benzimidazol-4-one and 2-aryl-2,3-dihydro-4H-[1,3]thiazino[3,2-a]benzimidazol-4-ones.…”

Section: 3-dihydro-4h-[13]thiazino[32-a]benzimidazol-4-one Was Obmentioning

confidence: 99%

“…The ease with which they are formed is probably explained by the fact that these compounds contain a conjugated system, and formation of such a system is an energetically favorable process. Probably conversions of thiazinobenzimidazolones 8a,b, leading to formation of cinnamic acid 17 or its amides, occurs according to a carbanion mechanism (the negative charge on the carbanions is on C (3) ). At the same time, the reactions of thiazinobenzimidazolone 1 possibly occurs according to a carbanion mechanism only in conversion of compound 5c to form 1,3-disubstituted benzimidazole-2-thione 6 and benzimidazole-2-thione 7.…”

Section: 3-dihydro-4h-[13]thiazino[32-a]benzimidazol-4-one Was Obmentioning

confidence: 99%

Some chemical properties of 2,3-dihydro-4H-[1,3]thiazino[3,2-a]benzimidazol-4-one and 2-aryl-2,3-dihydro-4H-[1,3]thiazino[3,2-a]benzimidazol-4-ones

Britsun

Esipenko

Lozinskii

2006

Chem Heterocycl Compd

Self Cite

View full text Add to dashboard Cite

“…

…”

mentioning

confidence: 99%

“…The reported methods for the synthesis of substituted pyrido[2,1-b] [1,3]thiazines are based on the reaction of 2-pyridinethiol with β-bromopropionic acid [1], reaction of tetrahydro-2-pyridinethione with benzylidenemalononitrile [2], reaction of 3,4-dihydropyridine-2(1H)-thione with epichlorhydrin [3], and acylation of 3,4-dihydro-2(1H)-pyridinethione with cinnamyl chloride [4].…”

mentioning

confidence: 99%

A simple and effective synthetic approach to pyrido[2,1-b]thiazines

Dyachenko

Chernega

2007

Chem Heterocycl Comp

View full text Add to dashboard Cite

The reported methods for the synthesis of substituted pyrido[2,1-b] [1,3]thiazines are based on the reaction of 2-pyridinethiol with β-bromopropionic acid [1], reaction of tetrahydro-2-pyridinethione with benzylidenemalononitrile [2], reaction of 3,4-dihydropyridine-2(1H)-thione with epichlorhydrin [3], and acylation of 3,4-dihydro-2(1H)-pyridinethione with cinnamyl chloride [4].In the present work, we have found a simple and efficient method for preparing previously unreported substituted, partially hydrogenated pyrido[2,1-b][1,3]thiazines 1-4 consisting of the regioselective alkylation of 2-pyridinethiols 5-7 and 2-pyridinethiolate 8 by 1,3-dibromopropane in DMF in the presence of aqueous KOH.An X-ray diffraction structural analysis of 3a was carried out to establish the regioselectivity of the alkylation of 2-pyridinethiols 5-8 by 1,3-dibromopropane. We found that there are two symmetrically independent molecules A and B in the crystal of this compound. The major geometrical parameters of these molecules are given in Table 1, while a general view of these molecules is given in Figs. 1 and 2. The bond lengths and bond angles in 3a(A) and 3a(B) are virtually identical. In particular, N (1) in both molecules has planar trigonal configuration: the sum of the bond angles at this atom is 359.0(6)° in 3a(A) and 359.9(6)° in 3a(B). In both molecules, the N (1) -C (4) and N (1) -C (8) bonds are markedly shortened relative to the standard value for the pure N(sp 2 )-C(sp 2 ) single bond (1.45 Å) [5] due to n(N (1) )-π(C (4) =C (5) ) and n(N (1) )-π(C (8) =O (1) ) conjugation. On the other hand, the conformations of these molecules differ considerably, as indicated both by the endocyclic torsion angles (Table 2) and the modified Kramer-Pople parameters, S, θ, and Ψ [6]. Thus, while the S (1) N (1) C (1) C (2) C (3) C (4) heterocycle in molecule A has chair conformation (S = 0.99, θ = 12.2°, ψ = 8.8°), this heterocycle in molecule B has twist-boat conformation (S = 0.82, θ = 65.0°, Ψ = 10.0°). The central N (1) C (4) C (5) C (6) C (7) C (8) ring in molecule A has close to half-boat conformation (S = 0.71, θ = 53.2°, Ψ = 24.2°), while this ring in molecule B has a conformation intermediate between half-boat and half-chair (S = 0.77, θ = 64.8°, Ψ = 15.7°). Furthermore, the arrangement of the endocyclic substituents differs significantly. Thus, __________________________________________________________________________________________

show abstract

Untitled

Cited by 8 publications

References 1 publication

Cycloacylation of thioamides and their derivatives by compounds containing an activated multiple bond (review)

Cycloacylation of thioamides and their derivatives by compounds containing an activated multiple bond (review)

Some chemical properties of 2,3-dihydro-4H-[1,3]thiazino[3,2-a]benzimidazol-4-one and 2-aryl-2,3-dihydro-4H-[1,3]thiazino[3,2-a]benzimidazol-4-ones

A simple and effective synthetic approach to pyrido[2,1-b]thiazines

Contact Info

Product

Resources

About