Total Synthesis of ( f ) - Fawcettimine Clayton
نویسنده
چکیده
quirement that 13 be converted to an enol, which is also a methylenecyclobutane totally shuts down turnover. That 13 is not a better inhibitor reveals the subtlety of the recognition of this enzyme for its substrate. The isoleucine precursor cu,p-dihydroxy-p-methylvaleric acid differs from 13 only by the addition of two hydrogens. The activity of vinyl fluoride 15, possibly acting as a stable enol surrogate, implicates an enol intermediate42 in the reaction mechanism of spinach DHAD. Empirical force field calculations on 15 and the putative enol 2 show a very close correspondence in structure. The extremely poor activity of oxamide 17 is disappointing, since in principle this should be an excellent enol mimic. These examples serve to illustrate the need for a larger data base to aid in inhibitor design.
منابع مشابه
Total synthesis of (+)-fawcettimine.
The fawcettimine class of Lycopodium alkaloids consists of over 60 natural products. Typically, these tetracyclic compounds contain a single quaternary carbon center and are derived biosynthetically from the lycopodane core through an oxidative rearrangement reaction. In 1959, the first member of this class, fawcettimine (1), was isolated by Burnell in the Blue Mountain Range of Jamaica. Inubus...
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