An anti-inflammatory and anti-microbial flavone glycoside from flowers of Cleome viscosa.

BACKGROUND: Natural products isolated from plant sources have been demonstrated as potential candidates against several ailments. The scientific investigations on the underlying principles of phytotherapy can pave way for the convergence of traditional medicines and modern science and technologies. RESULTS: Quercetin 3-O-(2''-acetyl)-glucoside obtained from ethyl acetate fraction of Cleome viscosa is studied against inflammatory of carrageenan-induced rat paw edema ( in vivo) and microbial activity on ( in vitro). The structure of the glycoside is confirmed by means of hydrogen-1 nuclear magnetic resonance spectroscopy, carbon nuclear magnetic resonance spectroscopy, attached proton test, and mass spectrum. The flavonoid glycoside showed significant anti-inflammatory activity of on carrageenan-induced rat paw edema ( in vivo) and anti-microbial activity ( in vitro) on Staphylococcus aureus (gram positive) and Escherichia coli (gram negative). The anti-inflammatory effect of the flavonoid glycoside may be due to the inhibition of prostaglandin synthesis. Selective toxicity with flavonoid glycoside towards the gram-positive bacteria was found on S. aureus. CONCLUSIONS: The present study reveals the anti-inflammatory and antimicrobial activities of an isolated quercetin 3-O-(2''-acetyl)-glucoside from a natural source ( C. viscosa).

2,6,6-Trimethyl-cyclo-hex-2-ene-carb-oxy-lic acid.

In the title crystal structure, C(10)H(16)O(2), inversion-related mol-ecules are linked by pairs of O-H⋯O hydrogen bonds involving carboxyl groups to form R(2) (2)(8) dimers. The cyclo-hexene ring displays a half-chair conformation.

2,6,6-Trimethyl-cyclo-hexene-1-carbaldehyde oxime.

In the crystal of the title compound C(10)H(17)NO, synthesized by the reaction of ß-cyclo-citral with hydroxyl-amine hydro-chloride, inversion-related mol-ecules are linked by a pair of O-H⋯N hydrogen-bonding inter-actions between the oxime functionalities, forming R(2) (2)(6) loops. The molecular conformation is stabilized by intra-molecular methyl C-H⋯N inter-actions. The cyclohexene ring has the typical half-chair conformation.

Dimethyl 2,2'-[(4-oxo-2-phenyl-4H-chromene-5,7-diyl)dioxy]diacetate: a more densely packed polymorph.

The title mol-ecule, C(21)H(18)O(8), crystallizes in two crystal polymorphs, see also Nallasivam, Nethaji, Vembu & Jaswant [Acta Cryst. (2009), E65, o314-o315]. The mol-ecules of both polymorphs differ by the conformation of the oxomethyl-acetate groups. The title mol-ecules are rather planar compared to the mol-ecules of the other polymorph. In the title mol-ecule, one of the oxomethyl-acetate groups is disordered (occupancies of 0.6058/0.3942). The structures of both polymorphs are stabilized by C-H⋯O and C-H⋯π inter-actions. Due to the planarity of the title mol-ecules and similar inter-molecular inter-actions, the title mol-ecules are more densely packed than those of the other polymorph.

Dimethyl 2,2'-[(4-oxo-2-phenyl-4H-chromene-5,7-di-yl)di-oxy]diacetate: a less densely packed polymorph.

The title mol-ecule, C(21)H(18)O(8), crystallizes in two crystal polymorphs, see also Nallasivam, Nethaji, Vembu & Jaswant [Acta Cryst. (2009), E65, o312-o313]. The main difference between the two polymorphs is in the conformation of the oxomethyl-acetate groups with regard to the almost planar [total puckering amplitude 0.047 (2) Å] chromene ring. In the title compound, the best planes of the oxomethyl-acetate groups through the non-H atoms are almost perpendicular to the chromene ring [making dihedral angles of 89.61 (6) and 80.59 (5)°], while in the second polymorph the mol-ecules are close to planar. Both crystal structures are stabilized by C-H⋯O.

5,7-Dimeth-oxy-2-phenyl-4H-chromen-4-one.

The asymmetric unit of the title compound, C(17)H(14)O(4), contains two independent mol-ecules which differ in the relative orientations of the phenyl rings with repect to the essentially planar [maximum deviations of 0.029 (2) and 0.050 (2) Šin the two mol-ecules] chromene fused-ring system, forming dihedral angles of 10.3 (5) and 30.86 (5)° in the two mol-ecules. The crystal structure is stabilized by weak C-H⋯O and C--H⋯π inter-actions, and π-π stacking inter-actions.

6,8-Dibromo-5-hydr-oxy-4-oxo-2-phenyl-4H-chromen-7-yl acetate.

In the title compound, C(17)H(10)Br(2)O(5), the chromene ring is almost planar with minimal puckering [total puckering amplitude = 0.067 (4) Å]. The dihedral angle between chromeme ring system and phenyl ring is 3.7 (2)°. The crystal structure is stabilized by intermolecular C-H⋯O inter-actions and an intramolecular O-H⋯O hydrogen bond also occurs.

5,7-Bis(benz-yloxy)-2-phenyl-4H-chromen-4-one.

In the title compound, C(29)H(22)O(4), the chromene ring is almost planar with a small puckering [0.143 (2) Å]. The crystal structure is stabilized by C-H⋯O and C-H⋯π inter-actions. Edge-to-face (centroid-centroid distances of 3.894 and 3.673 Å) and face-to-face (centroid-centroid distance of 3.460 Å) π-π-ring electron inter-actions are also observed.

2-Phenyl-5,7-bis-(prop-2-en-1-yl-oxy)-4H-chromen-4-one.

In the title compound, C(21)H(18)O(4), tthe dihedral angle between the chromene ring system and the pendant phenyl ring is 6.1 (1)°. The crystal structure is stabilized by an intermolecular C-H⋯O and C-H⋯π inter-actions.

4-Meth-oxy-5-[4-(4-meth-oxy-1,3-benzodioxol-5-yl)perhydro-1H,3H-furo[3,4-c]furan-1-yl]-1,3-benzodioxole.

The 1,3-benzodioxole ring systems in the title compound, C(22)H(22)O(8), are almost planar. The perhydro-furofuranyl system linking them adopts a distorted double-envelope conformation. Supra-molecular aggregation is effected by C-H⋯O, C-H⋯π and π-π [centroid-centroid distance of 3.755 Å, inter-planar distance of 3.633 Šand dihedral angle of 14.6°] inter-actions.