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Development of a Backbone Cyclic Peptide Library as Potential Antiparasitic Therapeutics Using Microwave Irradiation
Published on: January 26, 2016
Synthesis and anthelmintic activity of substituted (R)-phenyllactic acid containing cyclohexadepsipeptides
Peter Jeschke1, Jordi Benet-Buchholz, Achim Harder
1Bayer CropScience AG, Research & Development, Chemistry Insecticides, Monheim am Rhein, Germany. peter.jeschke@bayercropscience.com
Abstract:
The substituted (R)-phenyllactic acid containing cyclohexadepsipeptides (CHDPs) represent novel enniatin derivatives with strong in vivo activities against the parasitic nematode Haemonchus contortus Rudolphi in sheep. 2D NMR spectroscopic analysis revealed for the substituted (R)-phenyllactic acid containing CHDPs one major conformer with an unsymmetrically folded conformation lacking a cis-amide bond. A correlation between the substitution pattern and its anthelmintic activity was found. Here we report on a simple total synthetic pathway of the precursor for this particular type of CHDPs and an efficient modification of the benzylic side chain (R-PhLac(2)).
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