6-Methyl-2-phenyl-4,5-dihydro­pyridazin-3(2H)-one

In the title mol­ecule, C11H12N2O, the pyridazine ring has a skew-boat conformation. The dihedral angle between the phenyl ring [r.m.s deviation = 0.0039 (15) Å] and the best mean-plane of the pyridazine ring [r.m.s deviations = 0.2629 (15) Å] is 53.27 (10)°. In the crystal, mol­ecules are linked by C—H⋯O hydrogen bonds and C—H⋯π inter­actions involving the methyl group and the phenyl ring of a symmetry-related mol­ecule

N-[7-Eth­oxy-1-(prop-2-en-1-yl)-1H-indazol-4-yl]-4-methyl­benzene­sulfonamide

In the title compound, C19H21N3O3S, the C—SO2—NH—C torsion angle is 103.72 (11)°. The almost planar indazole ring [r.m.s. deviation = 0.0202 (14) Å] is twisted away from the methyl­benzene ring by 76.87 (7)°. The vinyl group is disordered over two orientations with site occupancies of 0.622 (10) and 0.378 (10). The S atom has a distorted tetra­hedral geometry [maximum deviation: O—S—O = 119.18 (11)°]. An intra­molecular C—H⋯O hydrogen bond occurs. In the crystal, two mol­ecules are linked about a center of inversion by pairs of N—H⋯O hydrogen bonds, generating a dimer. C—H⋯π inter­actions are also observed

N-[7-Eth­oxy-2-(prop-2-en-1-yl)-2H-indazol-6-yl]-4-methyl­benzene­sulfonamide

In the title compound, C19H21N3O3S, the C—SO2—NH—C torsion angle is 66.20 (9)°. The dihedral angle between the benzene ring and the essentially planar indazole ring system [r.m.s. deviation = 0.0361 (1) Å] is 72.97 (6)°. The S atom has a distorted tetra­hedral geometry [maximum deviation = O—S—O = 119.30 (6)°]. The crystal structure features inversion-related dimers linked by pairs of N—H⋯O hydrogen bonds. In addition, weak C—H⋯O inter­actions may stabilize the crystal packing

Ethyl 3-[7-eth­oxy-6-(4-meth­oxy­benzene­sulfonamido)-2H-indazol-2-yl]propano­ate

In the title compound, C21H25N3O6S, the dihedral angle between the meth­oxy­benzene and indazole rings is 74.96 (5)°. The crystal packing is stabilized by an N—H⋯O hydrogen bond into a two-dimensional network. In addition, C—H⋯π inter­actions and a π–π contact, with a centroid–centroid distance of 3.5333 (6) Å, are observed. The crystal packing is stabilized by N—H⋯O and C—H⋯O hydrogen bonds

N-(2-Formyl­phen­yl)-4-meth­oxy-N-(4-meth­oxy­phenyl­sulfon­yl)benzene­sulfonamide

In the title compound, C21H19NO7S2, the dihedral angles between the formyl­phenyl ring and the two meth­oxy­phenyl rings are 33.87 (9) and 41.00 (10)°. The S atoms have a distorted tetra­hedral geometry and the N atom shows a trigonally planar [r.m.s. deviation = 0.0437 (13) Å] coordination. The crystal structure is stabilized by inter­molecular C—H⋯O hydrogen bonds

Comparative spectroscopic and electrochemical study of N-1 or N-2-alkylated 4-nitro and 7-nitroindazoles

Abstract Our research groups are by long time involved in the study of the reactivity and the pharmacological activity of nitrogen-containing heterocyclic compounds: in this line we have now examined the behaviour of some substituted 4- and 7-nitroindazoles. Considering the fact that nitroreduction processes are often essential steps for the biological activity of nitro compounds and remembering that some nitroindazoles show interesting biological activities, we have collected nuclear magnetic resonance, electron spin resonance, and cyclic voltammetry data and carried out density functional theory computations on the above compounds thus obtaining an accurate picture of electronic distribution and reduction processes of the examined substrates as a function of their chemical structure. Looking also to our previous results obtained examining the behaviour of 5- and 6-nitroindazoles, we have confirmed the different general behaviour of 1- and 2-alkyl substituted nitroindazoles strictly related to the known different electronic distribution in these two classes of compounds. Interestingly, cyclic voltammetry data have confirmed the ability of N-1 H nitroindazoles to give rise to the formation of dimers, already observed by us studying 5- and 6-nitroindazoles

Alkylation and 1,3-Dipolar Cycloaddition of 6-Styryl-4,5-dihydro-2 H

Some new N-substituted pyridazinones and triazolo[4,3-b]pyridazinones were synthesized, respectively, by simple alkylation and 1,3-dipolar cycloaddition of pyridazin-3-one with nitrile imines. The regioselectivity of the reactions was ascertained by 1H, 13C NMR spectroscopy and X-ray diffraction of the synthesized compounds