El Mostapha Rakib

Chemical composition and antitumor activity of different wild varieties of Moroccan thyme

Many species of Thyme have been widely used in Moroccan folk medicine as anti-inflammatory, antioxidant and antinociceptive agents. This study was designed to examine the chemical composition and the in vitro antitumor activity of the essential oils and various extracts of thyme species collected in different regions of Morocco. The essential oil, obtained by hydrodistillation, and the various extracts, obtained by Soxhlet extraction, using solvents of varying polarity, were analysed by gas chromatography coupled to mass spectrometry (GC-MS). Both major and trace components were analysed. Overall, the major constituents in the chemical composition of Moroccan thyme populations were carvacrol, thymol, borneol and p-cymene. The rate of these components can hit respectively to 85%, 42%, 59%, and 23%. Furthermore, the essential oils as well as two pure products (carvacrol and thymol) were tested for their antitumoral activity against P815 mastocytoma cell line. While all these products showed a dose dependent cytotoxic effect, the carvacrol was the most cytotoxic one compared to the others. Interestingly, when these products were tested against the normal human peripheral blood mononuclear cells, they show a proliferative effect instead of a cytotoxic one.

Synthesis, antiproliferative and apoptotic activities of N-(6(4)-indazolyl)-benzenesulfonamide derivatives as potential anticancer agents.

Recently, it has been reported that compounds bearing a sulfonamide moiety possess many types of biological activities, including anticancer activity. The present work reports the synthesis and antiproliferative evaluation of some N-(6(4)-indazolyl)benzenesulfonamides and 7-ethoxy-N-(6(4)-indazolyl)benzenesulfonamides. All compounds were evaluated for their in vitro antiproliferative activity against three tumor cell lines: A2780 (human ovarian carcinoma) A549 (human lung adenocarcinoma) and P388 (murine leukemia). The results indicated that sulfonamides 2c, 3c, 6d, 8, 13, 3b and 16 were endowed with a pharmacologically interesting antiproliferative activity with compounds 2c and 3c showing the lower IC(50) (from 0.50 ± 0.09 to 1.83 ± 0.52 μM and from 0.58 ± 0.17 to 5.83 ± 1.83 μM, respectively). Moreover, these indazoles were able to trigger apoptosis through the upregulation of the typical apoptosis markers p53 and bax. As regard to the hypothetic targets of these compounds, a preliminary docking analysis showed that all compounds seemed to interact with β-tubulin, in particular compound 3b that showed the lower Ki. The cytofluorimetric analysis of the cell cycle phases indicates that all compounds, when administered at their IC(75), caused a block in the G2/M phase of the cell cycle with the generation of subpopulations of cells with a number of chromosome >4n. When the IC(50)s were applied we observed a prevalent block in the G0/G1 phase except for compounds 16 and 8 where a partial G2/M block was present with a concomitant decrease of cells in the G0/G1 and S phases of the cell cycle. Altogether these results suggest a possible, but not exclusive, interaction with microtubules.

Synthesis and antitumor activity of some substituted indazole derivatives.

Some new N‐[6‐indazolyl]arylsulfonamides and N‐[alkoxy‐6‐indazolyl]arylsulfonamides were prepared by the reduction of 2‐alkyl‐6‐nitroindazoles with SnCl2 in different alcohols, followed by coupling the corresponding amine with arylsulfonyl chlorides in pyridine. The newly synthesized compounds were evaluated for their antiproliferative and apoptotic activities against two human tumor cell lines: A2780 (ovarian carcinoma) and A549 (lung adenocarcinoma). Preliminary in vitro pharmacological studies revealed that N‐(2‐allyl‐2H‐indazol‐6‐yl)‐4‐methoxybenzenesulfonamide 4 and N‐[7‐ethoxy‐2‐(4‐methyl‐benzyl)‐2H‐indazol‐6‐yl]‐4‐methyl‐benzenesulfonamide 9 exhibited significant antiproliferative activity against the A2780 and A549 cell lines with IC50 values in the range from 4.21 to 18.6 µM, and also that they trigger apoptosis in a dose‐dependent manner. Furthermore, both active compounds were able to cause an arrest of cells in the G2/M phase of the cell cycle, typical but not exclusive of tubulin interacting agents, although only infrequent interactions with the microtubule network were observed by immunofluorescence microscopy, while docking analysis showed a possible different behavior between the two active compounds.

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

In the title compound, C19H21N3O5S·H2O, the central indazole system is essentially planar (r.m.s. deviation = 0.012 Å), while both the benzene ring and the mean plane defined by the non-H atoms of the ethyl propionic ester unit (r.m.s. deviation = 0.087 Å) are nearly perpendicular to the indazole plane, as indicated by the dihedral angles of 82.45 (8) and 75.62 (8)°, respectively. Consequently, the molecule adopts a U-shaped geometry. In the crystal, the water molecule, which is linked to the indazole system by a strong O—H⋯N hydrogen bond, is also involved in two additional N—H⋯O and O—H⋯O interactions, which link the organic molecules into chains along the b-axis direction.

STUDIES ON THE REDUCTION OF THE NITRO GROUP IN 4-NITROINDAZOLES BY ANHYDROUS SnCl2 IN DIFFERENT ALCOHOLS

Abstract The synthesis of new 7-alkoxy-4-amino-protected indazole and 4-amino-protected indazole derivatives by the reduction of the nitro group of 4-nitroindazoles using anhydrous stannous chloride in different alcohols is described.

N-(3-Chloro-1-methyl-1H-indazol-5-yl)-4-methylbenzene-sulfonamide.

The asymmetric unit of the title compound, C15H14ClN3O2S, contains two independent molecules showing different conformations: in one molecule, the indazole ring system makes a dihedral angle of 51.5 (1)° with the benzene ring whereas in the other, the indazole unit is almost perpendicular to the benzene ring [dihedral angle 77.7 (1)°]. In the crystal, the molecules are linked by N—H⋯N and N—H⋯O hydrogen bonds, forming a set of four molecules linked in pairs about an inversion centre.

N-(2-Allyl-4-chloro-2H-indazol-5-yl)-4-meth­oxy­benzene­sulfonamide hemi­hydrate

The fused five- and six-membered rings in the title compound, C17H16ClN3O3S·0.5H2O, are practically coplanar, with the maximum deviation from the mean plane being 0.057 (3) Å for the C atom bound to the exocyclic N atom. The indazole system makes a dihedral angle of 66.18 (12)° with the plane through the benzene ring, and it is nearly perpendicular to the allyl group, as indicated by the N—N—C—C torsion angle of 79.2 (3)°. In the crystal, the water molecule, lying on a twofold axis, forms O—H⋯N and accepts N—H⋯O hydrogen bonds. Additional C—H⋯O hydrogen bonds contribute to the formation of a chain along the b-axis direction.

N-(7-Eth­oxy-1H-indazol-4-yl)-4-methyl­benzene­sulfonamide

The molecule of the title heterocyclic compound, C16H17N3O3S, is bent at the S atom with an C—SO2—NH—C torsion angle of 80.17 (8)°. The phenyl substituent at the S atom is rotated out of the plane of the 1H-indazole ring [interplanar angle = 46.24 (8)°]. In the crystal, intermolecular N—H⋯N and N—H⋯O hydrogen bonds build up a ribbon developing parallel to the b-axis direction. C—H⋯O hydrogen bonds link these ribbons, forming a layer parallel to the bc plane.

N-[7-Eth-oxy-1-(prop-2-en-1-yl)-1H-indazol-4-yl]-4-methyl-benzene-sulfonamide.

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.

Synthesis and in-vitro cytotoxic evaluation of novel pyridazin-4-one derivatives.

A new series of N‐aryl‐4‐oxo‐1,4‐dihydro‐pyridazine‐3‐carboxylic acids has been synthesized by condensation of aryldiazonium with 4‐hydroxy‐6‐methyl‐2‐pyrone. Some of these compounds exhibited in‐vitro cytotoxic activity with moderate to excellent growth inhibition against the murine P815 mastocytoma cell line. Compound 5b showed an important cytotoxic activity against cell line P815 (IC50 = 0.40 μg/mL).