3 -isopropyl-morpholine-2,5-dione

The enzymatic ROP of six-membered cyclic depsipeptides 3(S)-isopropyl-morpholine-2,5-dione, 3(R)-isopropyl-morpholine-2,5-dione, 3(R,S)-isopropyl-morpholine-2,5-dione, (3S, 6R, S)-3-isopropyl-morpholine-2,5-dione, 3(S)-isobutyl-morpholine-2,5-dione, 3(S)-sec-butyl-morpholine-2,5-dione, 6(S)-methyl-morpholine-2,5-dione and 6(R,S)-methyl-morpholine-2,5-dione has been reported [60]. 

S)-isopropyl- morpholine-2,5-dione Porcine pancreatic lipase (10 wt%), M = 14300, PD = 1.07 by GPC against polystyrene standard. Reaction time 72 hours, conversion 92% at 120 C. [62]... 

Yonozawa N, Toda F, Hasegawa M (1985), Synthesis of polydepsipeptides ringopening polymerization of 6-isopropylmorpholine-2,5-dione and 6-isopropyl-4-methyl-morpholine-2,5-dione , Macromol. Rapid Commun., 6 (9), 607-611. 

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