Coumarin biosynthesis

Scheme 7.21 P450 oxygenation of amino acids in coumarin biosynthesis.

Karam, M.D. (2001) The role of the B/b allelic pair in coumarin biosynthesis in white sweetclover (Melilotus alba Desr.). Flonors Thesis, University of Iowa, USA. Kasahara, FI., Jiao, Y, Bedgar, D.L., Kim, S.J., Patten, A.M., Xia, Z.Q., Davina, L.B. and Lewis, N.G. (2006) Pinus taeda phenylpropenal double-bond reductase ... 

Laust, A.K. (2003) The role of the B/b allelic pair in the genetic regulation of coumarin biosynthesis in white sweetclover (Melilotus alba Desr.). Honors Thesis, University of Iowa, USA. 

As in coumarin biosynthesis involving phenylalanine oxygenation of p-coumaric acid in the ortho position is the key... 

Coumarin biosynthesis involves formation of PAL and 4-coumarate CoA ligase which is light and elicitor inducible. Cells of P. crispum respond by producing the linear furanocoumarins psoralen (17), bergapten (18), and xanthotoxin (19) (Fig. 9.6), as well as other furanocoumarins (Ellis, 1988). The relative amounts of furanocoumarins in the mixture was changed by use of different fungal elicitor sources. 

PouLTON, J. E., D. E. McRee, and E. E. Conn, Intracellular localization of two enzymes involved in coumarin biosynthesis in Melilotus alba. Plant Physiol., 65, 171-175 (1980). 

Elaboration of the 6,7,8 oxygenation pattern in simple coumarins Biosynthesis of puberulin in Agathosma puberula. Z. Naturforsch. 39c 31-37. 

SOME STRUCTURAL AND STEREOCHEMICAL ASPECTS OF COUMARIN BIOSYNTHESIS... 

Among the questions which arise when considering absolute configuration of coumarins in relation to biosynthesis are Do the changes in absolute configuration correlate with the nature of the chemical transformations in the various steps of coumarin biosynthesis Does the absolute configuration of oxidized isopentenyl substituted coumarins correlate with their botanical distribution Is there a simple biosynthetic model which can accommodate the occurrence of the different coumarin enantiomers as well as racemates ... 

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