28319-38-2Relevant articles and documents
Synthesis of the Mammea Coumarins. Part 4. Stereochemical and Regiochemical Studies, and Synthesis of (-)-Mammea B/BB
Crombie, Leslie,Jones, Raymond C. F.,Palmer, Christopher J.,Begley, Michael J.
, p. 353 - 358 (2007/10/02)
Acylation of phloroglucinol with (S)-2-methylbutyryl chloride followed by Pechmann condensation with ethyl 3-oxohexanoate, or acylation of 5,7-dihydroxy-4-propylcoumarin with (S)-2-methylbutyryl chloride gave an 8-(S)-acylcoumarin that was C-alkylated to afford natural (-)-mammea B/BB: the configuration of the 2-methylbutyryl moiety in the natural coumarins was thus demonstrated to be (S)-Surangin B was likewise prepared as a mixture of 1'S, 2''S)- and (1'R, 2''S)-stereoisomers.The crystal structure and conformation of a 6-acylcoumarin that establishes the orientation of other synthetic coumarins is reported.
Synthesis of the Mammea Coumarins. Part 3. The Insecticidal Coumarins of the Mammea E Series, Mammea D/BB, and a Dihydrocoumarin of the Mammea C Seies
Crombie, Leslie,Jones, Raymond C. F.,Palmer, Christopher J.
, p. 345 - 352 (2007/10/02)
A dihydrocoumarin metabolite of Mammea africana has been prepared by Lewis acid-mediated acylation of 5,7-dihydroxy-4-pentyl-3,4-dihydrocoumarin (available by hydrogenation of the corresponding coumarin).Acylation of 4-(1-methylpropyl)- and 4-(1-acetoxypropyl)-5,7-dihydroxycoumarin, each prepared by Pechmann condensation of phloroglucinol with the appropriate β-keto ester, gave 8-acylcoumarins that have been C-alkylated with 3-methyl-but-2-enyl bromide to provide, respectively, mammea D/BB (ferruol A), and the natural insecticidal 4-(1-acetoxypropyl) coumarins of M. americana, mammea E/BA and E/BB; C-alkylation with 3,7-dimethylocta-2,6-dienyl chloride of 4-(1-acetoxypropyl)-5,7-dihydroxy-8-(2-methylbutyryl)coumarin afforded surangin B, an insecticidal component of M.Iongifolia.
