Herbicidal Characteristics and Structural Identification of the Potential Active Compounds from sp. KRA17-580.

Weeds are notorious plant species exhibiting a harmful impact on crops. Biological weed control is an efficient and environmentally friendly technique, usually constitutes naturally derived compounds, including bioherbicidal metabolites produced by sp. The isolation and structural identification of phytotoxic compounds from have recently been proposed as an effective way to the discovery of novel bioherbicides.

Catalytic enantioselective synthesis of carboxy-substituted 2-isoxazolines by cascade oxa-Michael-cyclization.

An efficient quinidine-based phase-transfer-catalyzed enantioselective cascade oxa-Michael-cyclization reaction of hydroxylamine with various β-carboxy-substituted α,β-unsaturated ketones has been achieved for the preparation of chiral carboxy-substituted 2-isoxazolines. This cascade reaction provided the desired products in good yields (up to 98%) with excellent enantioselectivities (91-96% ee). In addition, the cascade reaction was effectively applied to the first catalytic asymmetric synthesis of the herbicide (S)-methiozolin.

(S)-[5-Methyl-3-(3-methyl-thio-phen-2-yl)-4,5-dihydro-isoxazol-5-yl]methanol.

In the title compound, C(10)H(13)NO(2)S, the thio-phene and isoxazoline rings are almost coplanar, the dihedral angle between their least-squares planes being 2.08 (1)°. The O-H atoms of the methyl hy-droxy group and the N atom of the isoxazole ring are orientated in the same direction to allow for the formation of inter-molecular O-H⋯N hydrogen bonds that lead to a supra-molecular chain along the a axis.

In vitro and ex vivo activity of new derivatives of acetohydroxyacid synthase inhibitors against Mycobacterium tuberculosis and non-tuberculous mycobacteria.

Sulfometuron methyl (SM) is an inhibitor of acetohydroxyacid synthase (AHAS), the first common enzyme in the branched-chain amino acid biosynthetic pathway, and shows activity against Mycobacterium tuberculosis both in vitro and in vivo. To develop AHAS inhibitor derivatives with more potent activity, 100 sulfonylurea analogues were screened for antimycobacterial activity against M. tuberculosis and non-tuberculous mycobacteria (NTM), and then evaluated for intracellular activity using mouse macrophages.