Detailed H-1 and C-13 NMR Spectral Data Assignment for Two Dihydrobenzofuran Neolignans

Author(s)

Medeiros, Talita C. T. ^[1] ; Dias, Herbert J. ^[1] ; Silva, Eliane O. ^[1] ; Fukui, Murilo J. ^[2] ; Soares, Ana Carolina F. ^[2] ; Kar, Tapas ^[3] ; Heleno, Vladimir C. G. ^[2] ; Donate, Paulo M. ^[1] ; Parreira, Renato L. T. ^[2] ; Crotti, Antonio E. M. ^[1]

Affiliation

^[1] Univ Sao Paulo, Fac Filosofia Ciencias & Letras Ribeirao Preto, Dept Quim, BR-14040901 Ribeirao Preto, SP - Brazil

^[2] Univ Franca, Nucleo Pesquisas Ciencias Exatas & Tecnol, BR-14404600 Franca, SP - Brazil

^[3] Utah State Univ, Dept Chem & Biochem, Logan, UT 84322 - USA

• Document type: Journal article
• Source: Journal of the Brazilian Chemical Society; v. 27, n. 1, p. 136-143, JAN 2016.
• Web of Science Citations: 5

Abstract

In this work we present a complete proton (H-1) and carbon 13(C-13) nuclear magnetic resonance (NMR) spectral analysis of two synthetic dihydrofuran neolignans (+/-)-trans-dehydrodicoumarate dimethyl ester and (+/-)-trans-dehydrodiferulate dimethyl ester. Unequivocal assignments were achieved by H-1 NMR, proton decoupled C-13 (C-13[1H]) NMR spectra, gradient-selected correlation spectroscopy (gCOSY), J-resolved, gradient-selected heteronuclear multiple quantum coherence (gHMQC), gradient-selected heteronuclear multiple bond coherence (gHMBC) and nuclear Overhauser effect spectroscopy (NOESY) experiments. All hydrogen coupling constants were measured, clarifying all the hydrogen signals multiplicities. Computational methods were also used to simulate the H-1 and C-13 chemical shifts and showed good agreement with the trans configuration of the substituents at C-7 and C-8. (AU)

• FAPESP's process: 13/20094-0 - Evaluation of the anti-parasitary and insecticidal activities of benzofuran derivatives, and study of their gas-phase fragmentation reactions using tandem mass spectrometry
• Grantee: Antônio Eduardo Miller Crotti
• Support Opportunities: Regular Research Grants
• FAPESP's process: 11/07623-8 - The use of quantum-mechanical methods to study the bonds and chemical interactions in self-organizing systems with applications in catalysis, medicinal chemistry, electrochromism, energy storage and conversion
• Grantee: Renato Luis Tame Parreira
• Support Opportunities: Research Grants - Young Investigators Grants
• FAPESP's process: 09/12202-1 - Antischistosomal and antileishmanial in vitro activities of some dihydrobenzofuran lignans
• Grantee: Murilo de Jesus Fukui
• Support Opportunities: Scholarships in Brazil - Master