Zinc oxide (ZnO)​: an efficient catalyst for the synthesis of 4-​arylmethylidene-​2-​phenyl 5(4H)​-​oxazolones having antimicrobial activity

A straightforward and a general method has been developed for the synthesis of some important functionalized 4-​arylmethylidene-​2-​phenyl-​5(4H)​-​oxazolone derivs. by combining araldehydes and hippuric acid in the presence of catalytic amt. of zinc oxide at room temp. in Et alc. is reported. The method was very easy, rapid and products obtained were in excellent yields. The compds. were purified, characterized and were subjected for in vitro antibacterial activity (detn. of Min. Inhibitory Concn. (MIC) by micro titrn. method) using two std. drugs Streptomycin and Ampicillin against Bacillus subtilis and Escherichia coli. Five of the synthesized compds. showed remarkable antibacterial activity when compared to that of stds

(2Z,3E)-2,3-Bis(2-thienylmethylene)-succinic acid methanol hemisolvate

In the title compound, C14H10O4S2·0.5CH3OH, the mol­ecule adopts a gauche conformation around the central C-C bond. Inter­molecular O-H...O hydrogen bonds between carboxyl groups link the mol­ecules into zigzag chains. Between chains, the thio­phene rings form [pi]-[pi] stacking inter­actions with a centroid-centroid distance of 3.98 Å. The methanol solvent mol­ecule forms an O-H...O hydrogen bond to one carboxyl group and is disordered about a crystallographic centre of inversion

The antimosquito properties of extracts from flowering plants in South Africa

Extracts of selected flowering plants, which are considered eco-friendly, are used for the treatment of numerous ailments and vector control worldwide. This has resulted in approximately 25 per cent of currently used drugs being derived from herbal sources. The aqueous and methanolic extracts of twelve plant species, Psidium guajava (pink fruit), Psidium guajava (white fruit), Psidium cattleianum var. cattleianum, Psidium guineense and Psidium X durbanensis, Achyranthes aspera, Alternanthera sessilis, Guilleminea densa, Capparis tomentosa, Leonotis leonurus, Dichrostachys cinerea and Carpobrotus dimidiatus, were tested for insecticidal activity, including larvicidal, adulticidal and repellent activities against the adult female mosquito, Anopheles arabiensis. The extracts of P. guajava (white fruit), C. tomentosa, L. leonurus,D. cinerea, and C. dimidiatus exerted a pronounced inhibitory effect on adult insects, while those of P. guajava (pink fruit), P. X durbanensis, P. cattleianum var. cattleianum, P. guineense, A. aspera, A. sessilis, and G. densa were ineffective and failed to satisfy the criteria set by the World Health Organization. In the tests for repellency against An. arabiensis, all the tested aqueous and methanolic plant extracts except those of A. sessilis repelled 80-100% of mosquitoes. The most effective mosquito repellents were the methanol and aqueous extracts of P. guajava (pink fruit), P. X durbanensis, P. cattleianum var. cattleianum, P. guineense, G. densa,L. leonurus and D. cinerea, which are potential sources of cost effective mosquito repellents to be utilized in malarial endemic areas.Fil: Chalannavar, R.K.. Durban University of Technology; SudáfricaFil: Hurinanthan, V.. Durban University of Technology; SudáfricaFil: Singh, Ajnesh. Durban University of Technology; SudáfricaFil: Venugopala, K.N.. Durban University of Technology; SudáfricaFil: Gleiser, Raquel M.. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Baijnath, H.. Durban University of Technology; SudáfricaFil: Odhav, B.. Durban University of Technology; Sudáfric