Jian-Yu Jin

Synthesis and Biological Activity of Some Novel Derivatives of 4-Amino-3-(D-galactopentitol-1-yl)-5-mercapto-1,2,4-triazole

To discover new 1,2,4-triazole derivatives which may possess significant biological activities, we synthesized a series of novel 6-aryl-3-(D-galactopentitol-1-yl)-7H-1,2,4-triazolo[3,4-b][1,3,4]thiadiazines and 4-(arylmethylidene)amino-5-(D-galactopentitol-1-yl)-3-mercapto-4H-1,2,4-triazoles from 4-amino-3-(D-galactopentitol-1-yl)-5-mercapto-1,2,4-triazole. All the title compounds were characterized by elemental analysis, IR, 1H- and 13C-NMR. Plant growth-regulating activity tests showed that these compounds have remarkable effects on the growth of radish and wheat.

Syntheses and Biological Activities of 6-Aryl-3-(3-hydroxy- propyl)-7H-1,2,4-triazolo[3,4-b][1,3,4]thiadiazines

A series of 6-aryl-3-(3-hydroxypropyl)-7H-1,2,4-triazolo[3,4-b][1,3,4]-thiadiazines were synthesized by the reaction of 4-amino-3-(3-hydroxypropyl)-5-mercapto-1,2,4-triazole (1) with substituted omega-haloacetophenones. Their structures were confirmed by elemental analysis, IR, 1H-NMR, and 13C-NMR. Tests of plant growth regulating effects showed that the title compounds display remarkable inhibitory activities on the growth of radish and wheat.

Synthesis and Biological Activities of Some Novel Triazolothiadiazines and Schiff Bases Derived from 1,2,4-Triazole

3-substituted-4-amino-5-mercapto-1,2,4-triazoles are versatile compounds for constructing various biologically active heterocycles. To find more 1,2,4-triazole derivatives that may possess significant biological activities, we synthesized a number of novel 3-(4-ethoxyphenyl)-6-aryl-1,2,4-triazolo[3,4-b][1,3,4]thiadiazines and 4-(arylmethylidene)amino-5-(4-ethoxyphenyl)-3-mercapto-4H-1,2,4-triazoles. All the title compounds were characterized by elemental analysis and NMR data, and the compound 5f was investigated with X-ray crystallography (CCDC No. 611639). The plant-growth regulating effects of those Schiff bases were examined, and they showed an inhibiting effect on the growth of wheat radicles and radish radicles.

Crystal structure of (E)-N-(4-(dimethylamino)benzylidene)-3-(2,4- dinitrophenylthio)-5-(4-methoxyphenyl)-4H-1,2,4-triazol-4-amine, C24 H21N7O5S

C 2 4 H 2 1 N 7 O 5 S , triclinio, PI (no. 2), a = 8.695(2) Â, b = 10.724(3) Â, c = 13.053(3) Â, a = 77.489(4)°, β = 89.409(4)°,γ = 88.171(4)°, V= 1187.6Â, Z = 2, Rgi(F) = 0.088, wRntfF) = 0.193, T= 298 K. Source of material The (£)-4-(4-(dimethylamino)-benzylideneamino)-3-(4methoxyphenyl)-1//-1,2,4-triazole-5(4W)-thione was synthesized by die reaction of 4-amino-3-(4-methoxyphenyl)-1 H-1,2,4triazole-5(4f/)-thione (0.005 mol) and 4-(dimethylamino)benzaldehyde (0.005 mol) with concentrated hydrochloric acid ( 1 ml) in ethanol (20 ml) refluxed for 3 h. And the triazole was prepared following the literature method of [1]. The title compound was prepared by the reaction of (£)-4-(4-(dimethylamino)benzylideneamino)-3-(4-methoxyphenyl)-l//-l,2,4-triazole5(4//)-thione (0.002 mol) and l-chloro-2,4-dinitrobenzene (0.002 mol) in the mixed solution of triethylamine (10 ml) and ethanol (20 ml). The mixture was refluxed for about 10 minutes and the desired product was obtained by filtration, drying and reciystallization from pyridine. Single crystals suitable for X-ray data collection were obtained by slow evaporation of a pyridine solution. 1.2 i/eq(parent atom), and d(Csp—H) = 0.96 or 0.97 Â with i/iso = 1.5 i/eq(parent atom). Discussion A few (£)-N-benzylidene-3-alkylthio-5-substituted-4/f-1,2,4triazol-4-amines have been reported to exhibit antifungal activity [2,3], antimicrobial properties [4,5], anticonvulsant activity [6], and antitumour effects [7]. It is to be expected that their arylsubstituted analogues (£)-N-benzylidene-3-arylthio-5substituted-4//-1,2,4-tri azoici-amines can exhibit the superposition of diversiform biological and pharmacological activities because they join aryl (containing heterocyclic radical), imine, thioether and other groups. One paper has showed (E)-Nbenzylidene-3-arylthio-5-substituted-4//-1,2,4-triazol-4-amines can be used as potential HIV-1 NNRTIs at present [8]. Therefore, the development of efficient methods for the synthesis of this class of compounds is of much importance. In the crystal structure of the title compound the bond lengths and angles are usual. The triazole ring and three benzene rings are each essentially planar. It is very interesting that the three benzene rings are approaching mutually perpendicular, and in the meantime the triazole ring and the two benzenes (C19-C24 and Cl 1-C16) are approximate mutually perpendicular, too. The dihedral angle between the benzene ring (C2-C7) and the triazole ring is only 23.1(2)°. In the triazole ring the bond length of NI—C8 (mean 1.322(5) Â) and N2—C9 (mean 1.309(5) Â) are obviously shorter than that of N3—C8 (mean 1.365(5) Â) and N3—C9 (mean 1.369(5) Â) [9-11], which indicates that the bonds of N1=C8 and N2=C9 are double ones while that of N3—C8 and N3—C9 are single ones. Table 1. Data collection and handling. Crystal: Wavelength:

Synthesis and structure of novel 1,2,4-triazole derivatives containing the 2,4-dinitrophenylthio group

Some novel 1,2,4-triazole derivatives containing the 2,4-dinitrophenylthio group have been synthesised in high yields by means of the reactions of 3-substituted-4-amino −1H-1,2,4-triazole-5(4H)-thiones or (E)-3-aryl-4-(benzylideneamino)-1H-1,2,4-triazole-5(4H)-thiones with 1-chloro-2,4-dinitrobenzene. The (E)-3-aryl-4-(benzylideneamino)-1H-1,2,4-triazole-5(4H)-thiones were prepared by the reaction of 4-amino-3-aryl-2H-1,2,4-triazole-3(4H)-thiones and diverse aromatic aldehydes. The 2, 4-dinitrophenyl group linked to the S atom, not to the N atom, was confirmed by the crystal structures. The structures of all the compounds were determined by elemental analysis, IR, MS, 1H NMR and 13C NMR.