Premium
Model Studies Towards a Novel Fragment Coupling for the Synthesis of Mycalamides and Related Natural Products
Author(s) -
Hoffmann Reinhard W.,
Breitfelder Steffen,
Schlapbach Achim
Publication year - 1996
Publication title -
helvetica chimica acta
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.74
H-Index - 82
eISSN - 1522-2675
pISSN - 0018-019X
DOI - 10.1002/hlca.19960790203
Subject(s) - chemistry , fragment (logic) , coupling (piping) , natural (archaeology) , combinatorial chemistry , stereochemistry , algorithm , mechanical engineering , engineering , archaeology , computer science , history
The mycalamides ( 3 ) and related natural products contain an α‐hydroxy acid 1 bound via an amide bond to an α‐alkoxy amine. The high density of functional groups in the ‘coupling region’ renders the coupling reactions delicate. Model studies showed that an alternate assembly of the molecular halves is possible using an ‘Umpolung’ of an α‐alkoxy isocyanate, e.g. 13 . Thus, combination of the ester 12 with 13 led to the α‐keto amide 16 . The further elaboration of 16 to the α‐hydroxy‐amide structure found in the mycalamides is reported.