169128-06-7Relevant articles and documents
Synthesis of Naturally (MM 47755; X-14881 E) and Non-Naturally Occuring Aromatic Angucyclinones
Krohn, Karsten,Khanbabaee, Karamali,Micheel, Joerg
, p. 1529 - 1538 (2007/10/02)
The Diels-Alder reactions of the naphthoquinones 1-4 with the dienes 5a-7 were investigated.The regioisomeric outcome of the adducts 10a-10g, 16, and 23 is in agreement with theoretical predictions from frontier orbital calculations.The adduct 10a was further converted to the non-natural (e.g. 15) and the adduct 16 to the natural angucyclinones MM 47755 (19a) and X-14881 E (22) by silicon-oxygen exchange and photooxygenation.The addition of naphthoquinones 2 and 4 to dienes 6 and 7 afford the Diels-Alder adducts 16 and 23, respectively, which are valuable intermediates for further transformation into non-aromatic angucyclinones. - Keywords: Angucyclinones / MM 47755 / X-14881 E / Diels-Alder reactions / Silicon-oxygen exchange