Byssochlamic acid

Another classical example is Stork s 1972 total synthesis of racemic byssochlamic acid (51), which constitutes the first application of a Beckmann fragmentation in the total synthesis of a complex natural product 1 Scheme S.131. Bicyclic oxime 49 underwent Beckmann fragmentation to generate the nine-membered intermediate 50, which was converted to ( )-byssochlamic acid (51) after ethyl substituent formation and conversion of the benzene rings to the two maleic anhydrides. 

Scheme 5.13 Beckmann fragmentation in the synthesis of byssochlamic acid.

White and coworkers used a Favorskii rearranjgement in their synthesis of the natural product ( )-byssochlamic acid 17. 4-Ethylcyclohexanone 18 synthesized by Jones oxidation of the corresponding alcohol, was carboxylated to 19 and then dibrominated to 20. The Favorskii rearrangement was carried out with NaOMe to form the unsaturated diester... 

Bromogeigerin acetate, T21 a-bromoisotutin, T31 iS-bromolactic acid, Al Browniine, K33 Brucine, K12 Bulbocapnine, K4 Bulbocodine, K3 Bulgarenes, T18 Bulnesol, T25 Bundlins, Y26 Buphanisine, K6 rerr-butylglycine, A24 Butyrospermol, T46 Buxenine G, K36 Buxidienine F, K36 Buxus alkaloids, K36 Byssochlamic acid, T58... 

C30H28O11, Xantholaccaic acid B ether dimethyl ester, 44B, 555 C3oH3oBr2NftOft, Byssochlamic acid bis(p-bromophenylhydrazide), 28, 564... 

A key step in a recent synthesis of (+)-byssochlamic acid involved cleavage of (100) at the central bridge to give (101) and its exo-methylene isomer, by oxime formation followed by reaction with phosphorous oxychloride in pyridine. ... 

SCHEME 20.9. The transannular [2+2] photo cycloaddition-cycloreversion in the synthesis of (+)-byssochlamic acid. 

The work that led to the constitution and stereochemistry of byssochlamic acid has been reviewed by J. K. Sutherland, Fortschr. Chem. Org. Naturst., 25, 131 (1967). 

Butyrospermol, T46 Buxenine G, K36 Buxidienine F, K36 Buxus alkaloids, K36 Byssochlamic acid, TS8... 

Although nutrient restriction is also conducive to the formation of spores (conidia) in P. urticae, there is no direct connection with patulin synthesis (Sekiguchi and Gaucher, 1977). Equally, in other species where the patulin pathway exists alongside independent pathways to other secondary metabolites, such as byssochlamic acid, the optimum conditions for one pathway may be significantly different from those for the other (Escoula, 1975). 

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