Scope of the 2(5H)-furanone helicity rule: a combined ECD, VCD, and DFT investigation

Author(s)

dos Santos, Jr., Fernando M. ^[1] ; Bicalho, Keylla U. ^[2] ; Calisto, Italo H. ^[1] ; Scatena, Gabriel S. ^[1] ; Fernandes, Joao B. ^[1] ; Cass, Quezia B. ^[1] ; Batista, Jr., Joao M. ^{[3, 1]}

Affiliation

^[1] Fed Univ Sao Carlos UFSCar, Dept Chem, BR-13565905 Sao Carlos, SP - Brazil

^[2] Sao Paulo State Univ UNESP, Inst Chem, BR-14800060 Araraquara, SP - Brazil

^[3] Fed Univ Sao Paulo UNIFESP, Inst Sci & Technol, BR-12231280 Sao Jose Dos Campos, SP - Brazil

• Document type: Journal article
• Source: ORGANIC & BIOMOLECULAR CHEMISTRY; v. 16, n. 24, p. 4509-4516, JUN 28 2018.
• Web of Science Citations: 6

Abstract

One of the most widely used methods to assess the stereochemistry of chiral 2(5H)-furanones is an empirical electronic circular dichroism (ECD) helicity rule. In the present work, an extensive experimental and theoretical investigation of the scope of the above-mentioned empirical rule for acetogenins with a hydroxyl group substituted at C-4 revealed a possible exception to this rule. The underlying causes for this observation are discussed with respect to side chain substitutions, conformational requirements, chromophore handedness as well as a qualitative orbital analysis. Further investigation using vibrational circular dichroism (VCD) spectroscopy led to the identification of spectral markers that seem to be more localized and less affected by side chain substitutions. As the presence of a ?-lactone ring and a hydroxyl group at C-4 is a very common structural feature of Annonaceous acetogenins, we recommend the combined use of ECD and VCD spectroscopy, along with quantum chemical computations, for the stereochemical analysis of structurally related molecules. (AU)

• FAPESP's process: 15/07089-2 - Vibrational chiroptical spectroscopy for stereochemical characterization of small molecules and macromolecules
• Grantee: João Marcos Batista Junior
• Support Opportunities: Scholarships in Brazil - Young Researchers
• FAPESP's process: 13/01710-1 - Enzyme ligand: new models of screening
• Grantee: Quezia Bezerra Cass
• Support Opportunities: Research Projects - Thematic Grants
• 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
• FAPESP's process: 10/18832-4 - Biomonitored studies of Spondia dulcis (Anacardiaceae), Annona montana and Rollinia mucosa (Annonaceae) against Atta sexdens rubropilosa, Leucoagaricus gongylophorus and Sitophilus zeamais and development of nanoencapsulation processes.
• Grantee: Keylla Utherdyany Bicalho
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 12/25299-6 - Integrated studies for leaf cutting control
• Grantee: João Batista Fernandes
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 16/23794-0 - Stereochemistry of complex natural compounds by vibrational optical activity: acetogenins
• Grantee: Fernando Martins dos Santos Junior
• Support Opportunities: Scholarships in Brazil - Post-Doctoral