70669-05-5Relevant academic research and scientific papers
Chemical synthesis of tripeptide thioesters for the biotechnological incorporation into the myxobacterial secondary metabolite argyrin via mutasynthesis
Siebert, David C.B.,Sommer, Roman,Pogorevc, Domen,Hoffmann, Michael,Wenzel, Silke C.,Müller, Rolf,Titz, Alexander
, p. 2922 - 2929 (2019)
The argyrins are secondary metabolites from myxobacteria with antibiotic activity against Pseudomonas aeruginosa. Studying their structure–activity relationship is hampered by the complexity of the chemical total synthesis. Mutasynthesis is a promising approach where simpler and fully synthetic intermediates of the natural product’s biosynthesis can be biotechnologically incorporated. Here, we report the synthesis of a series of tripeptide thioesters as mutasynthons containing the native sequence with a dehydroalanine (Dha) Michael acceptor attached to a sarcosine (Sar) and derivatives. Chemical synthesis of the native sequence D-Ala-Dha-Sar thioester required revision of the sequential peptide synthesis into a convergent strategy where the thioester with sarcosine was formed before coupling to the Dha-containing dipeptide.
A general method for the facile synthesis of optically active 2-substituted piperazines via functionalized 2,5-diketopiperazines
Ashton, Kate S.,Denti, Mitchell,Norman, Mark H.,St. Jean Jr., David J.
supporting information, p. 4501 - 4504 (2014/08/05)
Upon utilization of some common methods described in the literature for the synthesis of chiral, 2-substituted 2,5-diketopiperazines, extensive racemization was observed. Further investigation showed that heating in the presence of a mild base racemized the chiral center in the product diketopiperazines. A generalized, readily scalable route was sought and, after investigating the effect of base and temperature, conditions were identified that promoted cyclization without erosion of enantiomeric excess. An array of functionalization was tolerated and this procedure serves as a useful and reliable method for the facile synthesis of this important class of compounds.
Synthetic studies on glycopeptides concerned with defense response of plants. I. Syntheses of supprescins A and B
Kanemitsu, Takuya,Ogihara, Yukio,Takeda, Tadahiro
, p. 643 - 650 (2007/10/03)
Two glycopeptides, supprescins A and B, that suppress the production of pisatin, a phytoalexin of pea, were synthesized. In the synthesis of supprescin A, condensation of 3,4,6-tri-O-acetyl-2-azido-2-deoxy-α-D- galacto-pyranosyl trichloroacetimidate or its glycosidic β isomer with N- (carbobenzoxy)-L-seryl-O-benzyl-L-seryl-glycine methyl ester was carried out in the presence of trimethylsilyl trifluoromethanesulfonate (TMSOTf) to give the monoglycosyl tripeptide derivatives. For the synthesis of supprescin B, glycosylation of 2,3,4,6-tetra-O-acetyl-α-D-galactopyranosyl bromide and 1,2,3,6-tetra-O-benzoyl-α-D-galactopyranose was promoted by silver trifluoro-methanesulfonate (AgOTf) to provide a disaccharide derivative. The coupling of diglycosyl imidate, 2,3,4,6-tetra-O-acetyl-β-D-galactopyranosyl- (1→4)-3,6-di-O-benzoyl-2-azido-2-deoxy-D-galactopyranosyl trichloroacetimidate, and N-(carbobenzoxy)-L-seryl-O-benzyl-L-seryl-glycyl- 4-benzyl-L-aspartyl-5-benzyl-L-glutamyl-O-benzyl-L-threonine methyl ester in the presence of TMSOTf afforded the diglycosyl hexapeptide derivatives. Reduction, followed by N-acetylation, and then removal of the remaining protecting groups afforded the desired supprescin B.
