Yusoff M, Kwong HC, Quah CK. Crystal structure of 4-({(1E,2E)-3-[3-(4-fluoro-phen-yl)-1-isopropyl-1H-indol-2-yl]allyl-idene}amino)-5-methyl-1H-1,2,4-triazole-5(4H)-thione

The title compound, C23H22FN5S, exists in a trans conformation with respect to the methene C=C and the acyclic N=C bonds. The 1,2,4-triazole-5(4H)-thione ring makes dihedral angles of 88.66 (9) and 84.51 (10)°, respectively, with the indole and benzene rings. In the crystal, mol-ecules are linked by pairs of N-H⋯S hydrogen bonds, forming inversion dimers with an R 2 (2)(8) ring motif. The dimers are linked via C-H⋯π inter-actions, forming chains along [1-10]. The chains are linked via π-π inter-actions involving inversion-related triazole rings [centroid-centroid distance = 3.4340 (13) Å], forming layers parallel to the ab plane.

Cyanoacetamide MCR (III): three-component Gewald reactions revisited

Cyanoacetic acid derivatives are the starting materials for a plethora of multicomponent reaction (MCR) scaffolds. Here we describe valuable general protocols for the synthesis of arrays of 2-aminothiophene-3-carboxamides from cyanoacetamides, aldehydes or ketones, and sulfur via a Gewald-3CR variation. In many cases the reactions involve a very convenient work up by simple precipitation in water and filtration. More than 40 new products are described. We foresee our protocol and the resulting derivatives to become very valuable to greatly expanding the MCR scaffold space of cyanoacetamide derivatives.

Synthesis of a Novel Heterocyclic Ring System: Imidazo[3,2-D] [1,2,4]Triazolo[3,4-B][1,3,4]Thiadiazine

Synthesis of the novel compounds 3-substituted-6-arylimidazo[3,2-d][1,2,4]triazolo[3,4-b][1,3,4]thiadiazines was achieved by the reaction of 6-amino-3-substituted-7H-[1,2,4]triazolo[3,4-jb][1,3,4]thiadiazines with 4-substituted-phenacyl bromides in refluxing ethanol.

The First Example of a Diastereoselective Thio-Ugi Reaction: A New Synthetic Approach to Chiral Imidazole Derivatives

The first example of a diastereoselective thio-Ugi reaction with chiral alpha-methylbenzylamine is described. The reaction results in formation of two diastereomers of thioamides, the major of which was isolated. We have found that under similar conditions stereochemical results of the thio-Ugi reaction are opposite to stereochemical results of the Ugi reaction. Several chiral thioamides were synthesized. The reaction of thioamides with ammonia results in substituted amidines, which can be cyclized to imidazole derivatives in aqueous HCl. The synthesis of chiral imidazole derivatives was elaborated. Using certain approaches, both isomers of a key synthon in the synthesis of SB203386 (an orally bioactive HIV-1 protease inhibitor) were prepared. The scope, limitations, and stereochemistry of the approach are discussed.

1H and 13C NMR spectral characterization of some novel 7H-1,2,4-triazolo[3, 4-b] [1,3,4] thiadiazine derivatives

Some novel 1, 2, 4-triazolo[3,4-b][1,3,4]thiadiazines derivatives were synthesized. The complete (1)H and (13)C NMR chemical shift assignments were analyzed on one- and two-dimensional NMR techniques, including DEPT, NOE-DIF, COSY, HMBC, and HSQC.

Synthesis antimicrobial and antifungal activity of some new 3 substituted derivatives of 4-(2,4-dichlorophenyl)-5-adamantyl-1H-1,2,4-triazole

The synthesis of a series of substituted hydrazones and thiazolidinones is described, starting from N-[4-(2,4-dichlorophenyl)-5-adamantyl-1H-1,2,4-triazol-3-ylmercaptoacetyl]hydrazine. The new compounds were tested for antimicrobial and antifungal activity and some of them exhibited moderate activity against Candida albicans.

Synthesis of some halogen-containing 1,2,4-triazolo-1,3,4-thiadiazines and their antibacterial and anticancer screening studies--part I

A series of 7-arylidene-6-(2,4-dichloro-5-fluorophenyl)-3-substituted-1,2,4-triazolo[3,4-b]-1,3,4-thiadiazines (3) were prepared by the condensation of 4-amino-5-mercapto-3-substituted-1,2,4-triazoles (1) and 3-aryl-1-(2,4-dichloro-5-fluorophenyl)-2-bromo-2-propen-1-one (2). An alternative route for the synthesis of the title compound 3 has been described. The newly synthesised compounds were characterised on the basis of N-analyses, IR, 1H NMR and mass spectral data. Some of the newly synthesised compounds were tested for their antibacterial activities against Gram + ve and Gram - ve bacteria. Among the tested compounds 3n showed the highest degree of antibacterial activity against S. aureus and evaluation of the LD50 value of this compound was carried out. Some of the newly synthesised compounds were also screened for their anticancer activities. Among these, compounds 3b, 3g, 3n and 3p are found to be active against NCI-H460 (lung), MCF7 (breast), SF 268 (CNS) in the preliminary anticancer screening studies. Further, 60-cell-line anticancer studies of these compounds were carried out. The results of such studies are discussed in this paper.

Unsymmetrical cyclic ureas as HIV-1 protease inhibitors: novel biaryl indazoles as P2/P2' substituents

The preparation of unsymmetrical cyclic ureas bearing novel biaryl indazoles as P2/P2' substituents was undertaken, utilizing a Suzuki coupling reaction as the key step. Compound 6i was equipotent to the lead compound of the series SE063.

Synthesis and evaluation of heterocyclic carboxamides as potential antipsychotic agents

Heterocyclic analogues of 1192U90, 2-amino-N-(4-(4-(1,2-benzisothiazol-3-yl)-1-piperazinyl)-butyl) benzamide hydrochloride (1), were prepared and evaluated as potential antipsychotic agents. These analogues were evaluated in vitro for their binding to the dopamine D2, serotonin 5-HT2, and serotonin 5-HT1a receptors and in vivo for their ability to antagonize the apomorphine-induced climbing response in mice. Nine different types of heterocyclic carboxamides were studied in this investigation (i.e., pyridine-, thiophene-, benzothiophene-, quinoline-, 1,2,3,4-tetrahydroquinoline-, 2,3-dihydroindole-, indole-, benzimidazole-, and indazolecarboxamides). Two derivatives exhibited potent in vivo activities comparable to 1: 3-amino-N-(4-(4-(1,2-benzisothiazol-3-yl)-1-piperazinyl)butyl)-2 -pyridinecarboxamide (16) and 3-amino-N-(4-(4-(1,2-benzisothiazol-3-yl)-1-piperazinyl)butyl) -2-thiophenecarboxamide (29). Furthermore, these derivatives were found to be much less active in behavioral models predictive of extrapyramidal side effects than in the mouse climbing assay, which predicts antipsychotic activity. Carboxamides 16 and 29 were selected for further evaluation as potential backup compounds to 1.