Showing papers in "Journal of Heterocyclic Chemistry in 1993"

TL;DR: In this paper, the synthesis of 10-aryl-3,4,6,7,9,10hexahydro-1,8(2H,5H)-acridinedione as a new class of laser dyes is reported.

TL;DR: In this paper, a pyrazole ring with a 5-trifluoromethyl substituent was constructed by reaction of 4-alkoxy-1,1, 1, 1-trifi-oro-3-alken-2-ones (1) and hydrazine, methylhydrazine and phenylhydrazines (2) in good yields.

TL;DR: Several thieno[2,3-d]pyrimidines have been prepared by intramolecular cyclisation of 6-(substituted methylthio)-5-pyrimidine carbaldehyde and carbonitrile intermediates derived from 6-chloropyrimidine-5-carbaldehydes and 5-carbonitriles and methyl thioglycolate or 5-formylpyridine-4-(3H)-thiones and appropriate α-halogeno compounds as discussed by the authors.

TL;DR: In this paper, trifluoromethyl-substituted pyrazoles were synthesized via 1,3-dipolar cycloaddition from sydnones 2a-j and 1-aryl-3,3, 3-trifluoro-propynes 5a-f.

TL;DR: For example, this article showed that 3,6-diamino-1,2,4,5-tetrazine 1,4-dioxide can be oxidized with 3-chloroperoxybenzoic acid (MCPBA) to obtain 3-S,S-dimethylsulfoximino)-6-nitroso-1.2, 4,5,5tetra- zine.

TL;DR: In this article, a variety of 1,3 and 1,5-donor-acceptor substituted pyrazole derivatives have been synthesized by the cyclocondensation of a,b-ethynyl ketones with substituted phenyl hydrazines.

TL;DR: In this article, the addition of methylhydrazine to a variety of haloalkyl-substituted α,β-unsaturated esters gave 1,5-disubstituated 3-hydroxypyrazoles, in contrast to the more common synthesis from β-ketoesters, which gives 1,3-dissubstitized 5hydroxyrazole, and the regiochemical preference in this addition is considered on the basis of steric, electronic and mechanistic factors.

TL;DR: In this article, a shorter synthesis of 2′-deoxy-2′-methylthiouridine analogs 5, −5-methyluridine 6, -cyti-dine 15, − 5-methylcytidine 16, -adenosine 27 and -guanosine 34 was accomplished.

TL;DR: Phenothiazin-5-ium tetraiodide hydrate (2) was treated with two equivalents of a dialkylamine to give 3-(dialkylamino)phenothia-5 -ium triiodides (3-6).

TL;DR: A number of N- and C-alkyl derivatives of selected guanine analogs have been synthesized as potential antiviral agents as discussed by the authors, including 6-hexyl and 6-hydroxyhexyl derivatives.

TL;DR: In this article, cyclopentanone is condensed with phenylhydrazones 5, or oximes 6, in the presence of zinc dust, sodium propionate and propionic acid at 150° to give cyclopenta[b]pyrroles 7 in good yields.

TL;DR: Tetrahydro carbazoles have been prepared in one-flask syntheses from indoles, ketones or aldehydes, and maleimides, with acid catalysis as discussed by the authors.

TL;DR: In this article, the β-L-xylo-furanosyl analogues of the naturally occurring nucleosides have been synthesized and their antiviral properties examined.

TL;DR: A series of 4aminomethyl-1,2,3,4-tetrahydroisoquinoline derivatives were prepared as potential CNS-agents acting via amino acid neurotransmitter systems as mentioned in this paper.

TL;DR: In this article, N-(α-Benzotriazolylalkyl)arylacetamides, readily available from an arylacetamide, an aldehyde and benzotrizol, undergo intramolecular cyclization under acidic conditions to give 1-aryl-1,4-dihydro-3(2H)-isoquinolinones in good yields.

TL;DR: In this article, the reactions of β-keto sulfoxide, β-keto sulfones, or β -keto phosphinate with 1,1-disubstituted ethenes in the presence of manganese(III) acetate and molecular oxygen yielded 4-phenylsulfinyl-, 4-sulfonyl-, or 4-phosphinoyl-1,2-dioxan-3-ols 3 in moderate-to-good yields.

TL;DR: A series of 2,5-dibenzoxazolylphenols and related compounds were prepared by condensation of hydroxy- and methanesulfonamidoterephthalic acids with 2-aminophenols as discussed by the authors.

TL;DR: In this paper, it was shown that 5-Aroylamino-3H-1,3,4-thiadiazole-2-thiones can exist in two tautomeric forms, a thiol form and a thione form.

TL;DR: In this paper, the reaction of 2-(alkylamino)-3-(trifluoroacetyl)butenedioates (2a-b) with alkyl and aryl hydrazines in ether provides 1,6-dihydro-6-oxo- 3-( trifluoromehtyl)-4-pyridazinecarboxylates as their alkylamine salts (3a-g).

TL;DR: In this paper, the synthesis of several new thieno[3,4-d]pyrimidine C-nucleosides 5-8 is described, including a 5-ribosyl-ated methyl 4-(formylamino)thiophene-3-carboxylate key intermediate.

TL;DR: The oxidative cyclization of some aldehyde semicarbazones with four different oxidizing agents has been investigated in this paper, and it was shown that the structure and nature of cyclizing agent affected the rate and yield of cyclization but they did not show any influence on the regiochemistry of reaction.

TL;DR: H-1,2-Dithiolo[3,4-b]pyridine-3-thione reacts with primary alkylamines to give 1, 2-dihydro-2-thioxo-3 pyridinecarbothioamides 11a-g and two minor products (12a g and 13a g) as mentioned in this paper.

TL;DR: For example, this paper showed that 5-substituted 1-aryl-1H-pyrazole-4-acetonitriles and 4-methyl-1-phenyl-1 H-pyrrrhine-3-carboxylates can be obtained by reaction with potassium cyanide in dimethylsulfoxide solution.

TL;DR: In this paper, the AM1 calculation of 2-aminofuran (1a) is reported and the results are consistent with observed properties and are shown to be consistent with the observed properties.

TL;DR: A new series of potent uridine phosphorylase inhibitors have been prepared from barbituric acid, and among them, 1-[(2-hydroxyethoxy)methyl]-5-)(m--benzyloxy)benZylbarbiturics acid (37, BBBA) is the most promising having a Ki value of 1.1 ± 0.2 nM.

TL;DR: In this article, ten new pyrazoles have been prepared and their 13 C nmr chemical shifts compared with those of twelve other pyrazole, some of them prepared purposely for this study.

TL;DR: Ozaphyrin this article was synthesized by a McMurry coupling of 5,5′-diformyl-4,4-dipropyl-2,2′-bipyrrole (1) with 2,5-bis(5-formyl- 4-propylpropyl2-pyrrolyl)furan (5), which consists of layers of planar, staggered macrocycles stacked perpendicular to the α-axis.

TL;DR: In this article, the authors showed that when 2,4-dioxooctanoate (1) was reacted with phenylhydrazine hydrochloride, 3-butyl-1-phenyl- 1H-pyrazole-5-carboxylate (4) was favored over the corresponding 5butyl 1,1,phenyl 1H,1H,pyrazine-3 carboxylates (5) by a ratio of at least 6:1, a complete reversal of the regioselectivity observed for 1.

TL;DR: In this article, the synthesis of various N-1 substituted ethyl 4-pyrazolecarboxylates via reaction of ethyl 2-formyl-3-oxo-propionate (= ethoxycarbonylmalondialdehyde) with appropriately substituted hydrazines is described.

TL;DR: A series of 1,3-bis(1H-azol-1-yl)-2-aryl-2-propanols 17 were synthesized in an one-pot procedure by reacting l-aryl 2-(1,2,4-triazol)-l-yl) with dimethylsulfoxonium methide as mentioned in this paper.