Synthetic Studies toward Actinorhodin and γ-Actinorhodin by using a Homo-coupling Strategy: Synthesis of Hemiactinorhodin and Hemi-γ-actinorhodin
作者:Sandip V. Mulay、Amit Bhowmik、Rodney A. Fernandes
DOI:10.1002/ejoc.201500510
日期:2015.8
the synthesis of actinorhodin and γ-actinorhodin has been explored. The monomeric unit was synthesized by employing an efficient combination of Dotzbenzannulation and oxa-Pictet–Spengler reactions. Attempts towards oxidative homo-coupling of the pyranonaphthalene monomer intermediate to give dimer were unsuccessful. Later, monomer pyranonaphthalene was carried forward to complete the synthesis of hemiactinorhodin
作者:Rodney A. Fernandes、Sandip V. Mulay、Vijay P. Chavan
DOI:10.1016/j.tetasy.2013.10.011
日期:2013.12
A concise and efficient total synthesis of arizonins B1 and C1 is reported. A key building block alkyne is synthesized from a-glucono-S-lactone and used in the Dotz benzannulation reaction to construct the naphthalene unit. An oxa-Pictet-Spengler reaction gave the pyran ring while an H2SO4 mediated isomerization set the correct stereochemistry of the target molecules. Alternatively, a direct anti-pyran stereochemistry was prepared in a TFA solvent. The synthesis is competitive to previous reports and marks the first enantioselective synthesis of arizonin B1. (C) 2013 Elsevier Ltd. All rights reserved.