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15. Spectroscopic data for Na-DMNA-
9. Spectroscopic data for Na-(3,3-dimethyl-3H-indole-2-
D
-gHse(OBzl)-H (24):
yl)phenylalanine methyl amide (5): 1H NMR (CD3OD,
200 MHz): l ppm 7.32–6.89 (10H, m, Ar), 4.70 (1H, dd,
J=5.8 Hz, 9.2 Hz, CH), 3.28 (1H, dd, J=5.8 Hz, 13.8
Hz, Phe-CH2), 3.05 (1H, J=9.2 Hz, 13.8 Hz, Phe-CH2),
2.75 (3H, s, N-CH3), 1.36 (3H, s, CH3), 1.16 (3H, s,
CH3); 13C NMR (CD3OD, 200 MHz): 136.6, 128.5,
127.4, 126.8, 125.8, 120.9, 120.0, 114.3, 56.9, 37.3, 24.5,
23.3, 22.7; LC–MS (ESI): 322.0 (MH+).
1H NMR (CD3OD, 200 MHz) l ppm 7.93–7.29 (m, 9H,
Ar), 5.19 (t, 1H, J=6.6 Hz, CH), 4.95 (s, 2H, Bzl-CH2),
3.66 (t, 2H, J=6 Hz, CH2-O), 2.20 (dd, 2H, J=6.6 Hz, 6
Hz, CH2), 1.65 (s, 3H, CH3), 1.64 (s, 3H, CH3); 13C
NMR (CD3OD, 200 MHz): 177.3, 148.5, 137.6, 137.3,
128.2, 127.6, 127.3, 127.0, 124.7, 72.4, 64.6, 56.8, 30.9,
25.9, 25.7; LC–MS (ESI): 372.23 (MH+), 743.42 (2M+1).
Spectroscopic data for Na-Boc-Phe-gHse(OBzl)-DMNA
10. Typical procedure: Na-DMNA-amino acid or dipeptide
(1 mmol) in 10% HOAc in methanol (20 mL) was added
a catalytic amount of 10% Pd–C or PtO2. H2 was intro-
duced using a balloon and maintained for 30 min. The
catalyst was removed by filtration through Celite 545 and
the filtrate was concentrated and the product was isolated
either by flash column chromatography with an initial
ethyl acetate wash to remove all side products followed
by methanol to elute the desired product or by a cationic
exchange column eluted with 1% TEA in methanol.
11. Burke, S. D.; Danheiser, R. L. Handbook of Reagents for
Organic Synthesis. Oxidizing and Reducing Agents; Wiley:
New York, 1999; pp. 294–299.
12. No change was observed by TLC and HPLC when
Na-DMNA-phenylalanine methyl amide (1) was treated
with 50% TFA in CH2Cl2 or neat TFA for 30 min or 20%
piperidine in DMF for 48 h.
13. Fletcher, M. D.; Campbell, M. M. Chem. Rev. 1998, 98,
763–795.
1
(15): H NMR (CDCl3, 200 MHz): l ppm 7.24–7.84 (m,
14H, Ar), 5.05 (m, 1H, CH), 4.44 (s, 2H, Bzl-CH2), 4.36
(m, 1H, Phe-CH), 3.62–3.47 (m, 2H, CH2-O), 3.25 (dd,
1H, J=13.6 Hz, 5.2 Hz, Phe-CH2), 3.0 (dd, 1H, J=13.6
Hz, 8.6 Hz, Phe-CH2), 2.20 (m, 2H, CH2), 1.59 (s, 3H,
CH3), 1.54 (s, 3H, CH3), 1.38 (s, 9H, Boc); 13C NMR
(CDCl3, 200 MHz): 175.5, 171.6, 155.4, 149.3, 139.2,
137.9, 137.1, 133.2, 129.6, 128.7, 128.6, 128.1, 128.0,
126.8, 125.6, 79.9, 73.4, 66.5, 57.3, 55.8, 47.0, 38.2, 32.4,
28.4, 27.7, 27.4, LC–MS (ESI): 619 (MH+).
Spectroscopic data for Na-Boc-Phe-gHse(OBzl)-H·HCl
(22): 1H NMR (CD3OD, 200 MHz): l ppm 7.36–7.23 (m,
5H, Ar), 5.30 (m, 1H, CH), 4.53 (s, 2H, Bzl-CH2), 4.35
(dd, 1H, J=9.2 Hz, 6 Hz, Phe-CH), 3.6 (m, 2H, CH2-O),
3.1 (dd, 1H, J=13.6 Hz, 9.2 Hz, Phe-CH2), 2.8 (d, 2H,
Phe-CH2), 2.2 (m, 2H, CH2), 1.35 (s, 9H, Boc); 13C NMR
(CD3OD, 200 MHz): 173.4, 155.8, 137.4, 136.6, 128.7,
128.5, 127.6, 127.5, 127.0, 126.9, 125.9, 78.9, 72.3, 64.2,
55.7, 55.4, 31.2, 26.7; LC–MS (ESI): 411 (MH+−17),
428.18 (MH+), 450.1 (M+Na).
14. Pallai, P. V.; Richman, S.; Struthers, R. S.; Goodman,
M. Int. J. Pept. Protein Res. 1983, 21, 84–92.