. Author manuscript; available in PMC: 2013 Mar 1.

Published in final edited form as: J Pept Sci. 2012 Jan 16;18(3):155–162. doi: 10.1002/psc.1430

TABLE 1.

DTNP Deprotection Parameters and Results on Model Sec-Containing Peptides.

Protecting Group P	Peptide Synthetic Yield	Mass (m/z) M+H	Deprotection Conditions
Protecting Group P	Peptide Synthetic Yield	Mass (m/z) M+H	Eq. (mM) DTNP/TFA	Rxn Time/Temp.	% Deprotection/Cyclization (measured by HPLC) ^b

Mob (7)	46	675.9	0.38 (3.5)	1h/25 °C	100
Meb (8)	72	659.8	3.3 (30)	1h/25 °C	93
Bzl (9)	71	646.0	11 (100) ^a	1h/25 °C	90

Mob (10)	43	1346.0	2 (18)	1h/25 °C	98 ^b
Meb (11)	17	1314.3	20 (183) ^a	1h/50 °C	95 ^c
Bzl (12)	16	1308.1	20 (183) ^a	1h/50 °C	95 ^c

2% Thioanisole added.

From spontaneous cyclization.

From induced cyclization from bis-Npys intermediate.