Stereochemistry of spongosoritins: beyond optical rotation

Author(s)

Batista, Andrea N. L. ^[1] ; dos Santos, Jr., Fernando M. ^[1] ; Valverde, Alessandra L. ^[1] ; Batista, Jr., Joao M. ^[2]

Affiliation

^[1] Fluminense Fed Univ, Chem Inst, Dept Organ Chem, Outeiro Sao Joao Batista S-N, BR-24020141 Niteroi, RJ - Brazil

^[2] Univ Fed Sao Paulo, Inst Sci & Technol, Rua Talim 330, BR-12231280 Sao Jose Dos Campos, SP - Brazil

• Document type: Journal article
• Source: ORGANIC & BIOMOLECULAR CHEMISTRY; v. 17, n. 45, p. 9772-9777, DEC 7 2019.
• Web of Science Citations: 0

Abstract

Stereochemical determinations based solely on the comparison of optical rotation (OR) measured at a single wavelength may commonly result in misassignments. Herein, we use vibrational and electronic CD, NMR, OR, and DFT calculations, to confirm the absolute configuration (AC) of the cytotoxic marine polyketides spongosoritin A (1) and 9,10-dihydrospongosoritin A (2) as (-)-(6R,8R) and (-)-(6R,8S), respectively. The AC of natural 1 and 2 has so far relied upon comparisons of OR values only. Besides showing the dependence of OR on achiral structural features, such as E/Z double bond geometries, an IR spectral marker is provided to help distinguish the geometric isomers of related molecules. (AU)

• FAPESP's process: 14/25222-9 - Vibrational chiroptical spectroscopy for stereochemical characterization of small molecules and macromolecules
• Grantee: João Marcos Batista Junior
• Support Opportunities: Research Grants - Young Investigators Grants