No abstract

No abstract

No abstract

No abstract

No abstract

Structural Characterization of Vanchrobactin, a New Catechol Siderophore Produced by the Fish Pathogen Vibrio anguillarum Serotype O2. -(SOENGAS, R. G.; ANTA, C.; ESPADA, A.; PAZ, V.; ARES, I. R.; BALADO, M.; RODRIGUEZ, J.; LEMOS, M. L.; JIMENEZ*, C.; Tetrahedron Lett. 47 (2006) 39, 7113-7116; Dep. Quim. Fundam. Ind., Fac. Cienc., Univ. La Coruna, E-15071 La Coruna, Spain; Eng.) -Mais 03-203

Four natural lactylates of chlorinated fatty acids, chlorosphaerolactylates A−D (1−4), were isolated from the methanolic extract of the cyanobacterium Sphaerospermopsis sp. LEGE 00249 through a combination of bioassay-guided and MSguided approaches. Compounds 1−4 are esters of (mono-, di-, or tri)chlorinated lauric acid and lactic acid, whose structures were assigned on the basis of spectrometric and spectroscopic methods inclusive of 1D and 2D NMR experiments. High-resolution massspectrometry data sets also demonstrated the existence of other minor components that were identified as chlorosphaero(bis)lactylate analogues. The chlorosphaerolactylates were tested for potential antibacterial, antifungal, and antibiofilm properties using bacterial and fungal clinical isolates. Compounds 1−4 showed a weak inhibitory effect on the growth of Staphylococcus aureus S54F9 and Candida parapsilosis SMI416, as well as on the biofilm formation of coagulase-negative Staphylococcus hominis FI31.

The 1,3-butadiene motif is widely found in many natural products and drug candidates with relevant biological activities. Moreover, dienes are important targets for synthetic chemists, due to their ability to give access to a wide range of functional group transformations, including a broad range of C-C bond-forming processes. Therefore, the stereoselective preparation of dienes have attracted much attention over the past decades, and the search for new synthetic protocols continues unabated. The aim of this review is to give an overview of the diverse methodologies that have emerged in the last decade, with a focus on the synthetic processes that meet the requirements of efficiency and sustainability of modern organic chemistry.