Isolation and characterization of major diterpenes from C. canephora roasted coffee oil. Issue 14 (15th August 2016)

• Record Type: Journal Article
• Authors: Guercia, Elena; Berti, Federico; Navarini, Luciano; Demitri, Nicola; Forzato, Cristina
• Is Part Of: Tetrahedron, asymmetry. Volume 27:Issue 14/15(2016)
• Page Start: 649
• Page End: 656
• Publication Date: 2016-08-15
• Subjects: Asymmetry (Chemistry) -- Periodicals; 547.005
• DOI: 10.1016/j.tetasy.2016.06.008
• Languages: English
• ISSNs: 0957-4166

Abstract

Graphical abstract: Abstract: A simple laboratory procedure for the isolation of pure cafestol and 16- O -methylcafestol together with β-sitosterol from coffee is disclosed. Cafestol and 16- O -methylcafestol have been exhaustively characterized through 1D and 2D 1 H, 13 C NMR, CD and X-ray diffraction. For the first time, the molecular structure of cafestol is reported and the assignment of the absolute configuration is unequivocally given by exploiting anomalous scattering of a brominated derivative. Abstract : Cafestol: C20 H28 O3 Ee = n.d. [ α ]D 20 = −119 ( c 0.06, CH3 OH) Source of chirality: natural source Absolute configuration: (5 S, 8 S, 9 R, 10 S, 13 R, 16 R ) Abstract : 16- O -Methylcafestol: C21 H30 O3 Ee = n.d. [ α ]D 20 = −102 ( c 0.13, CH3 OH) Source of chirality: natural source Absolute configuration: (5 S, 8 S, 9 R, 10 S, 13 R, 16 R ) Abstract : p -Bromobenzoyl ester of cafestol: C27 H31 BrO4 Ee = n.d. [ α ]D 20 = −84.0 ( c 0.13, CHCl3 ) Source of chirality: natural source Absolute configuration: (5 S, 8 S, 9 R, 10 S, 13 R, 16 R )