New advances on anisotropic NMR and detection of bioactive marine natural product

Abstract

A summary of each chapter shall be presented below. Chapter 1: The use of anisotropic NMR in the structural analysis of chiral small molecules has expanded in recent years. Currently, Residual Dipolar Constants (RDC) can be applied as a standard tool in the efficient improvement of the determination of the relative configuration of small-sized compounds by standard NMR. In the present Thesis dissertation, we have developed another methodology of anisotropic NMR based on measures of anisotropy of residual chemical proton displacement (1H RCSA) that has been applied, firstly to compound-models, strychnine, estrone, retrorsine and [alfa]-santonin, and subsequently to new natural products: to an isolated meroditerpene of the brown alga Sargassum muticum, the trichloromaminades A and B isolated from the non-edible fungus Tricholoma equestre and, finally to a briarane of marine origin isolated from the gorgonian Briareum asbestinum collected from the peninsula of Yucatan (México). Chapter 2: The detection and quantification of natural products present in traces in complex mixtures is still an active field of research for chemists. Since the introduction of the Orbitrap® mass detector into the market, a revolution in analytical detection techniques has begun. In this Doctoral Thesis we have taken advantage of this technology for the detection and, in some cases, the isolation and quantification of natural products of marine origin of biological interest. The different approaches in the LC / HRMS techniques used were applied to: Detection and isolation of siderophore production in several pathogenic marine bacteria: vanchrovatin type in three Vibrio species, piscibactin type in a mutant strain of Vibrio alginolyticus, the siderophore produced by the bacteria Edwardsiella tarda and Photobacterium damselae subsp. damselae Detection and quantification of AHLs in three pathogenic Vibrio species. Detection of TTX in the fish Diodon hystrix collected in El Salvador.