Abstract
AbstractThe deuterium‐labeled racemic 3‐(trans‐2‐nitrocyclopropyl)‐alanine (rac‐[D2]‐3) and 3‐(trans‐2‐aminocyclopropyl)alanine (rac‐[D2]‐4) as well as non‐labeled rac‐3‐[trans‐2‐(hydroxycarbonyl)cyclopropyl]alanine (rac‐5a) and rac‐3‐[trans‐2‐(methoxycarbonyl)cyclopropyl]alanine (rac‐5b) were prepared in 43, 18, 88 and 49 % overall yield, respectively, along a general synthetic route applying alkylations of the lithium enolate of tert‐butyl (diphenylmethylene)‐aminoacetate (O’Donnel’s glycine equivalent 11) as a key step. Feeding experiments with these amino acids and Streptomyces griseoflavus (strain W 384) revealed that rac‐[D2]‐3, rac‐5a and rac‐5b are incorporated to give hormaomycin 1b and its analogue 23, respectively, while rac‐[D2]‐4 is not. Feeding of rac‐2‐(trans‐2‐nitrocyclopropyl)glycine (rac‐6) unexpectedly gave the 5‐nitronorvaline‐containing hormaomycin analogues 25a–c. This is rationalized as arising from a cyclopropyl to homoallyl anion rearrangement followed by enzymatic hydrogenation of the double bond. These experiments provided new insights into the substrate specificity of the enzyme which assembles hormaomycin. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
