01260nas a2200157   4500008004100000245012400041210006900165260000800234300001400242490000700256520062200263100002600885700003500911700002800946856012800974       2017                        eng d00aNovel silaproline (Sip)-incorporated close structural mimics of potent antidepressant peptide drug rapastinel (GLYX-13)0 aNovel silaproline Sipincorporated close structural mimics of pot  cAPR  a1568-15710 v583 aRapastinel (GLYX-13) is a C-amidated tetrapeptide drug under clinical development for adjunctive treatment of major depressive disorder (MDD). Rapastinel features two consecutive proline residues centered at the peptide sequence (Thr-Pro-Pro-Thr-NH2), which are detrimental to its biological activity. In this communication, we report the synthesis of very close structural analogues of rapastinel comprising silaproline (Sip) as proline surrogate. By virtue of its enhanced lipophilicity and metabolic stability, Sip introduction in the native rapastinel sequence is expected to improve its pharmacokinetic profiles.1 aMadica, Krishnaprasad1 aNadimpally, Krishna, Chaitanya1 aSanjayan, Gangadhar, J.  uhttps://library.ncl.res.in/content/novel-silaproline-sip-incorporated-close-structural-mimics-potent-antidepressant-peptide