The crystal structures of (Z)-1-phenyl-4-[((2-phenylhydrazono)methyl)]-1H-1,2,3-triazole, (Z)-4-[(2-(2,4-dimethylphenyl)hydrazono)methyl]-2-phenyl-2H-1,2,3-triazole, (E)-4-[(2-(2,4-dinitrophenyl)hydrazono)methyl]-2-phenyl-2H-1,2,3-triazole, and (E)-N'-((2-phenyl-2H-1,2,3-triazol-4-yl)methylene)isonicotinohydrazide dihydrate are reported. The formations of (Z)- configurations about the C=N bonds in the first two compounds arise from the stabilizing presence of intramolecular N-H···N hydrogen bonds, while in the third compound, the presence of intramolecular N-H···O hydrogen bonds promotes an (E) geometry. The arrangement about the CONHC=N fragment in the hydrated acylhydrazone is EC(O)NH/EC=N. Also present in (E)-N'-((2-phenyl-2H-1,2,3-triazol-4-yl)methylene)isonicotinohydrazide is an interesting R44(8) ring formed from hydrogen bonds generated from four water molecules. Significant π···π stacking interactions are exhibited in three compounds, but not in the least planar first compound, in which the dominant intermolecular interactions are C-H···π interactions. Other intermolecular interactions in one of the compounds are C-H···π interactions, in another compound are C-H···O hydrogen bonds and N-O···π interactions, and in the last compound are O-H···X (X = O and N), N-H···O and C-H···O hydrogen bonds.

Este artigo descreve a síntese e a atividade antileishmania de novos derivados pirazolil benzenossulfonamídicos. Estes foram elucidados por métodos espectrométricos. Alguns compostos mostraram uma atividade in vitro significativa contra Leishmania amazonensis, destacando-se o derivado 1e. Nenhum dos derivados pirazolil benzenossulfonamídicos mostraram qualquer toxicidade em macrófagos murinos.

This paper describes the synthesis and the antileishmanial activity of new pyrazolyl benzenesulfonamide derivatives. These were elucidated by spectrometric methods. Some compounds showed a significant in vitro activity against Leishmania amazonensis, highlighting the derivative 1e. These pyrazolyl benzenesulfonamide derivatives did not show any toxicity in murine macrophage.

Um método mais suave e eficiente é descrito para a síntese de 3-(2'-aminoaril)pirazóis, a partir das reações de 4-cloroquinolinas com hidrazina em excelentes rendimentos. Estas reações de abertura de anel heterocíclico ocorrem em condições mais suaves do que as descritas anteriormente.

We describe a mild and efficient method for the formation of 3-(2'-aminoaryl)pyrazoles in excellent yields from reactions of 4-chloroquinolines with hydrazine. These heterocyclic ring opening reactions occur under much milder conditions then previously described.

Este trabalho apresenta uma investigação teórico-experimental dos espectros infravermelho/Raman de diversos metais representativos coordenados com 1,3-ditiol-2-tiona-4,5-ditiolato (dmit), a saber [NEt4]2[Zn(dmit)2], [NEt4][Sb(dmit)2] e [NEt4][Bi(dmit)2]. Os espectros IV/Raman de todos os sólidos e também o espectro IV em solução do composto [NEt4]2[Zn(dmit)2] foram registrados de 4000 a 100 cm-1. Duas regiões foram claramente identificadas: abaixo de 380 cm-1 os modos apresentaram forte contribuição metal-ligante, e acima, os modos indicaram majoritária contribuição do ligante. Os espectros IV/Raman do NEt4Br também foram registrados. As bandas vibracionais foram atribuídas a partir da análise de compostos relacionados, de publicações prévias e comparadas com amplo conjunto de cálculos ab initio realizados com diversos ECPs (SBK, Sttutgart), conjunto de bases (com e sem funções d) e metodologias (RHF, DFT e MP2). As geometrias, freqüências e intensidades foram calculadas e comparadas com as freqüências experimentais visando atribuições seguras. Assim, uma excelente concordância foi obtida para diversas bandas experimentais.

This work reports a theoretical-experimental investigation of the infrared/Raman vibrational spectra of several metal 1,3-dithole-2-thione-4,5-dithiolate (dmit) complexes; [NEt4]2[Zn(dmit)2], [NEt4][Sb(dmit)2] and [NEt4][Bi(dmit)2]. IR/Raman spectra of all the solids and the solution IR spectrum of [NEt4]2[Zn(dmit)2] were recorded from 4000 to 100 cm-1. Two regions were clearly identified: below 380 cm-1, the modes presented significant metal-ligand contributions, and above, the modes indicated major ligand contributions. IR/Raman spectra of NEt4Br have also been recorded. The vibrational bands have been assigned starting from the analysis of related compounds, of previous published spectra and compared to several ECPs (SBK, Stuttgart), basis sets (with and without functions d) and methodologies (RHF, MP2 and DFT). Geometries, frequencies and intensities were calculated and compared to the experimental frequencies seeking secure assignment. Thus, an excellent agreement was obtained for several experimental bands.

O composto [(HOCH2)3CNHC(O)]2 (1), formado a partir da reação de (HOCH2)3CNH2 com EtOC(O)C(O)OEt, reage com aldeídos aromáticos ArCHO, gerando como produtos bis-alquilideno simétricos, N,N'-bis(2-Ar-5-ROCH2-1,3-dioxan-5-a)etanodiamides 3 (Ar = Ph, p-MeC6H4 or p-MeOC6H4, R = H). Uma reação similar com Me2CO produziu N'-bis(2,2-dimethil-5-hidroximetil-1,3-dioxan-5-a)etanodiamida (2). Enquanto três estereoisômeros (Z,Z)-, (Z,E)- e (E,E)-3 (Ar = Ph, R = H) foram formados a partir da reação de 1 com PhCHO, somente (Z,Z)-3 (Ar = p-MeC6H4 ou p-MeOC6H4, R = H) foi isolado quando 1 reagiu com ArCHO (Ar = p-MeC6H4 ou p-MeOC6H4). As conformações Z têm os grupos: aril- equatorial, HOCH2- equatorial e amido-axial, no sólido e em solução, enquanto as conformações E têm os grupos aril- equatorial, amido- equatorial e HOCH2-axial. Uma mistura na proporção 1:1 de (Z,Z)-: (E,E)-3 (Ar = Ph, R = H) co-cristaliza. As energias de conformação de (Z,Z)- e (E,E)-3 (Ar = Ph, R = H) e 1 foram determinadas por cálculos de mecânica molecular. O estereoisômero (Z,Z)-3 (Ar = Ph, R = H) é mais reativo do que o (E,E) em reações de alquilação: somente o estereoisômero (Z,Z)-3 (Ar = Ph, R = Ph3SnCH2) foi isolado da reação de uma mistura de (Z,Z)- e (E,E)-3 (Ar = Ph, R = H) com Ph3SnCH2I. Quando uma mistura 1:1 de (Z,Z)- e (E,E)-3 (Ar = Ph, R = H) foi reagida com um excesso de brometo alílico, uma mistura na proporção de 4:3 de (Z,Z)- e (E,E)-3 (Ar = Ph, R = H2C=CHCH2) foi isolada. Reação de oxomercuração de (Z,Z)- e (E,E)-3 (Ar = Ph, R = H2C=CHCH2) com Hg(OAc)2 em metanol, seguida por uma troca aniônica utilizando NaCl, produziu um único estereoisômero, {N-(Z)-[[(R²)-5-(3-cloromercuria-2-metoxipropil)oximetil]-2-fenil-1,3-dioxan-5-il]}{ N'-(Z)-[[(S²)-5-(3-cloromercúria-2-metoxipropil)oximetil]-2-fenil-1,3-dioxan-5-il]}etanodiamida (4) que foi caracterizado por cristalografia de raio X.

Compound, [(HOCH2)3CNHC(O)]2 (1), obtained from (HOCH2)3CNH2 and EtOC(O)C(O)OEt, reacts with aryl aldehydes, ArCHO, to give the symmetric bis-alkylidene derivatives, N,N'-bis(2-Ar-5-ROCH 2-1,3-dioxan-5-yl)ethanediamides 3 (Ar = Ph, p-MeC6H4 or p-MeOC6H4, R = H). A similar reaction with Me2CO produced N'-bis(2,2-dimethyl-5-hydroxymethyl-1,3-dioxan-5-yl)ethanediamide (2). While three stereoisomers, (Z,Z)-, (Z,E)- and (E,E)-3 (Ar = Ph, R = H), were formed from 1 and PhCHO, only (Z,Z)-3 (Ar = p-MeC6H4 or p-MeOC6H4, R = H) was isolated from ArCHO (Ar = p-MeC6H4 or p-MeOC6H4) [the Z conformations in the solid state and in solution have equatorial-aryl, equatorial-HOCH2 and axial-amido groups: E forms have equatorial-aryl, equatorial-amido and axial-HOCH2 groups]. A 1:1 mixture of (Z,Z)-:(E,E)-3 (Ar = Ph, R = H) co-crystallises. Molecular mechanics calculations have been carried out on the conformation energies of (Z,Z)-and (E,E)-3 (Ar = Ph, R = H) and 1 and support the crystallographic and spectral findings. The stereoisomer, (Z,Z)-3 (Ar = Ph, R = H), is more reactive in alkylation reactions than the (E,E)-form: only (Z,Z)-3 (Ar = Ph, R = Ph3SnCH2) was isolated from the reaction of a mixture of (Z,Z)- and (E,E)-3 (Ar = Ph, R = H) with Ph3SnCH2I. From the reaction of excess allyl bromide with a 1:1 mixture of (Z,Z)- and (E,E)-3 (Ar = Ph, R = H), a 4:3 mixture of (Z,Z)- and (E,E)-3 (Ar = Ph, R = H2C=CHCH2) was isolated. Oxymercuriation of (Z,Z)-3 (Ar = Ph, R = H2C=CHCH2) with Hg(OAc)2 in MeOH, followed by anion exchange using NaCl, produced the single stereoisomer, {N-(Z)-[[(R²)-5-(3-chloromercuri-2-methoxypropyl)oxymethyl]-2-phenyl-1,3 -dioxan-5-yl]}{N'-(Z)-[[(S²)-5-(3-chloromercuri-2-methoxypropyl)oxymethyl]-2-phenyl-1,3-dioxan -5-yl]}ethanediamide (4), characterised by X-ray crystallography.