Prosopis glandulosa

The natural occurrence of promelacacinidins was until recently restricted to the heartwoods of Prosopis glandulosa and Acacia melanoxylon. The investigations of the heartwood constituents of A. caffra and A. galpinii also revealed the presence of a limited number of promelacacinidins (Table 11.11) as well as mixed di- and trimeric proteracacinidin or promelacacinidins (see Table 11.10). 

Johnson H. B. and Mayeux H. S. (1990) Prosopis glandulosa and the nitrogen balance of rangelands extent and occurrence of nodulation. Oecologia 84, 176-185. 

Prosopis glandulosa currently dominates the overstory in upland and lowland woody plant communities. Depending on patch type, it constitutes 40-90% of the above-ground biomass (Archer and Boutton, unpublished) and 30-70% of the coarse root (>l-mm diameter) biomass (WAtts, 1993). As such, the dynamics of P. glan-... 

Two teracacidol-catechin dimers linked (4)ff->8) and (4)ff- 6) have been synthesized, but these compounds have not been reported as natural products (27, 28). A melacacidol-(4a- 6)-melacacidol dimer isolated from the heartwood of Prosopis glandulosa (mesquite) occurs in low concentration together with the oxidatively coupled flavan-3-ols described previously (174). Foo (103) has recently isolated a melacacinidin-(4a->6)-isomelacacidin dimer from Acacia melanoxylon, the first natural product that has the 2i ,3i ,4i -(2,3-d5-3,4-c/5)-stereochemistry. However, only its 2R,3R,4S (2y3-cis-3,4-t ans) diastereoisomer was obtained by synthesis. 

More recently, Roux and co-workers (149) have isolated a complex array of oligomeric polyphenols based on (2jR,3S)-3,3, 4, 7,8-pentahydroxyflavan from the heartwood of mesquite (Prosopis glandulosa). These include some oligomers linked by normal proanthocyanidin interflavanoid linkages (i.e. 4- 6), but predominantly the form of linkage has arisen from oxidative coupling to form biphenyl and m-terphenyl interflavanoid bonds. These are just the sort of bonds expected to be formed in secondary processes in any proanthocyanidin polymer, and it is still an open question as to the extent of these processes in outer bark and heartwood. 

Young D A, Brandt E V, Ferreira D, Roux D G 1986 Synthesis of condensed tannins. Part 17. Oligomeric (2/ ,3S)-3,3, 4, 7,8-pentahydroxy flavans Atropisomerism and conformation of biphenyl and w-terphenyl analogues from Prosopis glandulosa ( mesquite ). J Chem Soc Perkin Trans I 1737-1749... 

Black Logwood Hematoxylin campechianum) complex of sumac, pinon gum, yellow ochre) Datura stramonium Sumac (Rhus trilobata) Honey mesquite roots (Prosopis glandulosa) ... 

Figure 17 Alkaloids of Prosopis glandulosa prosopilosidine (813) prosopilosine (814) isoprosopilosidine (815) or (816) isoprosopilosine (817) or (818) A -ju jprosopine (819).

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