71901-40-1Relevant academic research and scientific papers
Three new metabolites from the marine yeast Aureobasidium pullulans
Shigemori,Tenma,Shimazaki,Kobayashi
, p. 696 - 698 (1998)
Two new diketopiperazines (1 and 2) with a D-cis-4-hydroxyproline residue, and orcinotriol (3), a new 1,3-dihydroxyphenol derivative, were isolated from cultured broth of the yeast Aureobasidium pullulans, which was isolated from an Okinawan marine sponge. The structures of the compounds, including their absolute stereochemistries, were determined by spectroscopic data and chemical means.
Enantioselective synthesis of 3-methylisochromans and determination of their absolute configurations by circular dichroism
Kerti, Gabor,Kurtan, Tibor,Illyes, Tuende-Zita,Koever, Katalin E.,Solyom, Sandor,Pescitelli, Gennaro,Fujioka, Naoko,Berova, Nina,Antus, Sandor
, p. 296 - 305 (2007/10/03)
Seven (S)-3-methylisochromans with different substitution patterns on their aromatic rings, and hence with different directions of their sum electric transition moments, were synthesized by ring-closure of optically active (S)-1-arylpropan-2-ol derivatives. The (S)-1-arylpropan-2-ols were obtained by kinetic resolution and their absolute configurations were determined with the aid of a zinc porphyrin tweezer and by Mosher's method. A systematic CD study of substituted isochroman derivatives revealed that, unlike in the cases of chiral tetralin and 2,3-dihydrobenzo[b]furan chromophores, the presence of achiral substituents of large spectroscopic moment (e.g., OMe) on the aromatic ring does not change the helicity rule of the "unsubstituted" isochroman chromophore: (P)/(M) helicity of the isochromen heteroring resulted in positive/negative 1Lb band Cotton effects (CE) regardless of the nature(s) and position(s) of the substituent(s). (S)-3-Methylisochromans were oxidized at C-1, allowing access to the corresponding dihydroisocoumarins, in which positive CE of the n→-π* transitions were correlated with (P) helicity and (S) absolute configuration. On DDQ-assisted oxidation, two trans-1-methoxy-3-methylisochrornan derivatives were prepared and used to study the effect of the axial benzylic C-1 methoxy group on the conformation of the heteroring and the 1Lb band CE. Wiley-VCH Verlag GmbH & Co. KGaA, 2007.
