title: Stereochemistry of complex marine natural products by quantum mechanical calculations of NMR chemical shifts: solvent and conformational effects on okadaic acid.
abstract: Marine organisms are an increasingly important source of novel metabolites, some of which have already inspired or become new drugs. In addition, many of these molecules show a high degree of novelty from a structural and/or pharmacological point of view. Structure determination is generally achieved by the use of a variety of spectroscopic methods, among which NMR (nuclear magnetic resonance) plays a major role and determination of the stereochemical relationships within every new molecule is generally the most challenging part in structural determination. In this communication, we have chosen okadaic acid as a model compound to perform a computational chemistry study to predict 1H and 13C NMR chemical shifts. The effect of two different solvents and conformation on the ability of DFT (density functional theory) calculations to predict the correct stereoisomer has been studied.
authors.affiliation: University Institute of Bio-Organic Chemistry "Antonio González" (CIBICAN), Avda. Astrofísico Francisco Sánchez 2, La Laguna 38206, Spain. hdomrod@ull.es.
authors.forename: Humberto J
authors.initials: HJ
authors.lastname: Domínguez
authors.affiliation: University Institute of Bio-Organic Chemistry "Antonio González" (CIBICAN), Avda. Astrofísico Francisco Sánchez 2, La Laguna 38206, Spain. guillermo.diaz@ues.edu.sv.
authors.forename: Guillermo D
authors.initials: GD
authors.lastname: Crespín
authors.affiliation: University Institute of Bio-Organic Chemistry "Antonio González" (CIBICAN), Avda. Astrofísico Francisco Sánchez 2, La Laguna 38206, Spain. alu0100420050@ull.edu.es.
authors.forename: Adrián J
authors.initials: AJ
authors.lastname: Santiago-Benítez
authors.affiliation: University Institute of Bio-Organic Chemistry "Antonio González" (CIBICAN), Avda. Astrofísico Francisco Sánchez 2, La Laguna 38206, Spain. jgavin@ull.es.
authors.forename: José A
authors.initials: JA
authors.lastname: Gavín
authors.affiliation: University Institute of Bio-Organic Chemistry "Antonio González" (CIBICAN), Avda. Astrofísico Francisco Sánchez 2, La Laguna 38206, Spain. mnorte@ull.es.
authors.forename: Manuel
authors.initials: M
authors.lastname: Norte
authors.affiliation: University Institute of Bio-Organic Chemistry "Antonio González" (CIBICAN), Avda. Astrofísico Francisco Sánchez 2, La Laguna 38206, Spain. jjfercas@ull.es.
authors.forename: José J
authors.initials: JJ
authors.lastname: Fernández
authors.affiliation: University Institute of Bio-Organic Chemistry "Antonio González" (CIBICAN), Avda. Astrofísico Francisco Sánchez 2, La Laguna 38206, Spain. adaranas@ull.es.
authors.forename: Antonio Hernández
authors.initials: AH
authors.lastname: Daranas
mesh_terms: D000465:Algorithms; D000818:Animals; D001688:Biological Products / Q000737:chemistry*; D019295:Computational Biology; D018360:Crystallography, X-Ray; D004141:Dinoflagellida; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D008968:Molecular Conformation; D019319:Okadaic Acid / Q000737:chemistry*; D011789:Quantum Theory; D012997:Solvents; D013237:Stereoisomerism
chemical_list: D001688:Biological Products; D012997:Solvents; D019319:Okadaic Acid