Thermal Synthesis of Polypeptides from N-Butyloxycarbonyl Oligopeptides Containing Aspartyl Residue at C-Terminus

Table 3

Amino acid composition and D/L ratio of hydrolysates of the higher molecular weight fractions.

Substrate	Temperature/°C	Reaction time/h	Mw/Da	AA composition		D/L ratio		AA recovery/%
				AA	Asp	AA	Asp
Boc-Gly-L-Asp (5a)	110	24	4400	1.11	1.00	—	0.064	95
	120	24	7000	0.98	1.00	—	0.061	104
	130	1	2800	1.10	1.00	—	0.058	87
	130	2	4100	1.08	1.00	—	0.072	76
	130	4	6900	1.10	1.00	—	0.087	93
	130	8	7800	1.10	1.00	—	0.098	88
	130	16	5400	1.12	1.00	—	0.122	84
	130	24	4600	1.09	1.00	—	0.142	83
	150	2	2500	1.11	1.00	—	0.189	100
	170	2	1400	1.13	1.00	—	0.596	100
Boc-L-Ala-L-Asp (5b)	130	1	1500	1.00	1.00	0.042	0.067	88
Boc-L-Val-L-Asp (5c)	130	2	2200	0.94	1.00	0.017	0.099	78
Boc-Gly-Gly-L-Asp (5d)	120	4	7800	1.95	1.00	—	0.059	102