M. Raza Shah

Biological screening of selected flora of Pakistan

Methanolic extracts of different parts of five medicinal plants, Ferula assafoetidaL. resin, Grewia asiaticaL. leaves, Ipomoea hederaceaJacq. seeds, Lepidium sativumL. seeds and Terminalia chebulaRetz. fruits were tested in vitrofor their cytotoxic, phytotoxic, insecticidal, nematicidal and anthelmintic activities. Ipomoea hederaceashowed very significant phytotoxic and cytotoxic activity, with 100% inhibition of Lemna minorgrowth and 100% death of Artemia salinaat concentrations of 1000 and 100 µg mL-1. Grewia asiaticaexhibited very weak activities while Lepidium sativumand Ferula assafoetidashowed moderate to good potential in all three bioassays. The results suggest screening of Ipomoea hederaceaseeds further for isolation of bioactive compounds that may be responsible for its toxic potential.

Nepetolide: A New Diterpene from Nepeta suavis

A new tricyclic clerodane-type diterpene, nepetolide (1), has been isolated from Nepeta suavis along with three known compounds namely β -sitosterol, stigmasterol, and ursolic acid. The structure elucidation of the isolated compounds was based primarily on two-dimensional (2D)-NMR techniques including correlation spectroscopy (COSY), heteronuclear multiple quantum coherence (HMQC), and heteronuclear multiple bond correlation (HMBC) experiments.

Nepetanal and nepetanoate: a new diterpene aldehyde and a benzene derivative ester from Nepeta juncea.

One new tricyclic clerodane type diterpene aldehyde nepetanal (1) and one new benzene derivative nepetanoate (2) have been isolated from a plant Nepeta juncea together with two known compounds oleanolic acid (3) and ursolic acid (4). The structures of the isolated compounds were elucidated by means of modern spectroscopic techniques and comparison with literature data. Copyright

Benzyl 2-(4-bromo­anilino)-4,4-dimethyl-6-oxocyclo­hex-1-enecarbodithio­ate: first triclinic polymorph

The six-membered cyclohexene ring in the title compound, C22H22BrNOS2, adopts an envelope conformation, with the C atom bearing the two methyl groups representing the flap. This atom deviates by 0.686 (4) Å from the plane passing through the other five atoms of the ring (r.m.s. deviation = 0.025 Å). The molecular conformation is stabilized by an intramolecular N—H⋯S hydrogen bond.

One new triterpene ester from Nepeta suavis

One new tetracyclic triterpene ester (1) has been isolated from the chloroform-soluble portion of the whole plant of Nepeta suavis along with two known compounds, namely artemetin (2) and jaceidin (3). The structures of the isolated compounds were assigned on the basis of their 1H and 13C NMR spectra including two-dimensional NMR techniques such as COSY, HMQC, and HMBC experiments and comparison with the literature data.

Di-tert-Butyl 2,2′-[2,2′-methyl­enebis(naphthalene-2,1-diyldi­oxy)]diacetate

In the title compound, C33H36O6, two naphthalene ring systems are connected through a methylene linkage [C—C—C = 114.9 (2)°]; the ring systems are aligned at an angle of 76.5 (1)°. Of the two –O–CH2–C(=O)–C(CH3)3 substituents, one adopts an extended conformation whereas the other is U-shaped. In the crystal, molecules are linked via weak C—H⋯O hydrogen bonding, forming supramolecular chains running along the c axis.

4-Bromo-1-nitro-benzene.

The non-H atoms of the title molecule, C6H4BrNO2, are essentially coplanar with an r.m.s. deviation of 0.040 Å. In the crystal, π–π stacking occurs between parallel benzene rings of adjacent molecules with centroid–centroid distances of 3.643 (3) and 3.741 (3) Å. Weak intermolecular C—H⋯O hydrogen bonding and short Br⋯O contacts [3.227 (4) 3.401 (4) Å] are also observed in the crystal structure. The crystal studied was a non-morohedral twin with a 26.1 (6)% minor component.

4,4'-Bis[(E)-(2,3-diiodo-prop-2-en-1-yl)-oxy]biphen-yl.

Iodine adds across both triple bonds of 4,4′-bis(prop-2-ynyloxy)biphenyl, yielding the 4,4′-bis(2,3-diiodoallyloxy)biphenyl title compound, C18H14I4O2; the 2,3-diiodoallyoxy substituents have the I atoms in an E configuration. In the biphenyl portion of the molecule, the aromatic rings are inclined by 37.8 (2)°.

tert-Butyl 2-(4-nitro-phen-oxy)acetate.

In the title molecule, C12H15NO5, the nitrophenoxy portion is approximately planar (r.m.s. deviation = 0.034 Å) and makes an angle of 84.8 (1)° with respect to the –CH2–C(=O)–O–C fragment. In the crystal, π–π stacking is observed between nearly parallel benzene rings of adjacent molecules, the centroid–centroid distance being 3.6806 (10) Å. Weak intermolecular C—H⋯O hydrogen bonding is present in the crystal structure.

n-Undeca­nyl 2-(4-chloro­anilino)-4,4-dimethyl-6-oxocyclo­hex-1-ene­carbo­dithio­ate

The six-membered cyclohexene ring in the title compound, C26H38ClNOS2, adopts an envelope conformation, with the C atom bearing the two methyl groups representing the flap. This atom deviates by 0.642 (4) Å from the plane passing through the other five atoms of the ring (r.m.s. deviation = 0.053 Å). The molecular conformation is stabilized by an intramolecular N—H⋯S hydrogen bond.