Sideroxylon

The flavonoid sideroxylonal B has been synthesised from 3,5-dimethoxyphenol through initial conversion to the 2-(3 -methylbutan-l -ol) derivative. Reaction with EtMgBr simultaneously generates the quinone methide and the 2-isopentenylphenol which react together to produce the flavan (Scheme 12) <99TL1925>. 

Manilkara solimoesensis Gilly Manilkara zapotilla Gilly and Manilkara chicle Gilly Micropholis (also known as Sideroxylon) spp. 

In studies of the decomposition of sawdusts in soils at 78°F., McKenzie (1958) observed that the maximum amounts of nitrogen taken up by mountain ash (Eucalyptus regnans F. Muell), red ironbark (Eucalyptus sideroxylon A. Cunn) and radiata pine (Pinus radiata D. Don) were 1.6, 1.4 and 1.0% respectively. He states that it is possible that these amounts are inversely related to degree of lignification of the wood, and this would account for softwoods causing less uptake than eucalypts, and a dense eucalypt less uptake than a less dense one. Maximum uptake was reached in 5-11 weeks and the immobilized nitrogen was released very slowly over a period of many weeks. 

Hart J H, Hillis W E 1974 Inhibition of wood rotting fungi by stilbenes and other polyphenols in Eucalyptus sideroxylon. Phytopathology 64 939-948... 

Hillis W E, Hart J H, Yazaki A 1974 Polyphenols of Eucalyptus sideroxylon wood. Phytochemistry 13 1591-1595... 

Hillis W E, Isoi K 1965 Variation in the chemical composition of Eucalyptus sideroxylon. Phytochemistry 4 541-550... 

Durability of heartwood is dependent on the kinds and concentration of extractives present, their chemical stability, and their resistance to microbial inactivation. Many tree species (e.g., Madurapomifera or Robiniapseudoacacia) contain only one or two toxic compounds, often in very small quantities, yet the wood is extremely durable (45, 54). In other species a number of similar toxic compounds may occur together (Libocedrus decurrens (5)), or toxic compounds of a very different chemical nature may be present in the heartwood of a single species (stilbenes and ellagitannins in Eucalyptus sideroxylon (23). In either case, the combination of compounds acts additively or perhaps even synergistically to produce an inhibitory environment. 

Planchonella ihyrsoidea C. T. White andP. anteridifera H. J. Lam (Sideroxylon anteridiferum C. T. White and Francis) (Sapotaceae)... 

Leguminosae Geoffroea, Mimozyganthus, Prosopis, Pterogyne Sapotaceae Sideroxylon... 

According to the acyl-polymalonate hypothesis, chain-starter units other than acetate may be involved in the biosynthetic process (c/. Scheme 1). In this connection, the naturally occurring stilbenes and derivatives are produced by condensation of a cinnamate unit with three malonate units followed by aldol condensation of the enzyme-bound P-triketo-ester intermediate (77). " Secondary transformations (p. 183) may also occur at a pre-aromatic or postaromatic stage in the biosynthesis. Previous attempts to demonstrate the intermediacy of P-triketo-esters in the biosynthesis of stilbenes resulted in the reported conversion of cinnamoyltriacetic acid (77 R = H, as acid) into pinosylvin (79) by acetone powders prepared from leaves of a mutant of Eucalyptus sideroxylon. However, a subsequent report has indicated that this conversion cannot be repeated and this has prompted the explanation that P-polyketo-ester intermediates are bound to the enzyme and do not occur in the free state. Several difTerent preparations of acetone powder from E. 

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