C. Guarise et al. / Tetrahedron 68 (2012) 4346e4352
4351
with 1 ml of a solution of acetic acid/trifluoroethanol/dichloro-
methane (1:2:6), twice for 15 min followed by washing.
FmocePEG(20)eOH (123 mg, 3.5 equiv), HOBT (30 mg), PyBOP
Research and Reference Reagent Program for providing non-
commercial reagents. The Padova group gratefully acknowledges
the support by MIUR (grant 2006039071) and by the University of
Padova (starting grant to L.J.P.).
(
0
115 mg), and DIEA (110
.3 ml of NMP and let to react overnight. After washing Fmoc was
deprotected. The coupling was performed with FmoceIsoeOH
177 mg, 7.5 equiv), PyBOP (266 mg), DIEA (140 l) in DMF (1 ml),
and NMP (0.3 ml). After Fmoc removal BSA (N,O-bis(trimethylsilyl)
acetamide; 61 l) in 1 ml of DCM was added and let to stir (15 min,
ml) were dissolved in 1 ml of DMF and
Supplementary data
(
m
m
rt) followed by washing with dichloromethane. FmoceAibeF was
synthesized dissolving 3.79 mmol (1.2 g) of FmoceAibeOH and
FmoceTrp(Boc)eOH in 25 ml of DCM and 7.6 mmol (0.61 ml) of
iyridine and 7.6 mmol (0.65 ml) of cyanuric fluoride, stirring for 1 h
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2 5
P O ; with the same procedure
1
FmoceTrp(Boc)eF was obtained from FmoceTrp(Boc)eOH.
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(
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after HPLC purification, 99% 24.6 min. ESI-MS: calculated:
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.4. Fusogenic activity assay
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This work was supported in part by NSF Career Award 0449842
to G.G. L.J.P. acknowledges financial support from the ERC (contract
UE-239898). We thank the National Institutes of Health AIDS
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