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This ee is not sufficient for incorporation
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Ee’s were determined by chiral
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Ee of 9 was
not determined.
<A NAME="RG13302ST-13">13</A> Literature precedent in a related
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1α: 1H
NMR (500 MHz, CDCl3): δ = 7.95 (b,
1 H, NH), 7.74 (q, J = 1.0 Hz,
1 H, H-6), 6.38 (dd, J = 8.3
and 1.8 Hz, 1 H, H-1′), 4.09 (d, J = 5.3
Hz, 1 H, H-3′), 3.78 (dd, J = 9.4
and 7.3 Hz, 1 H, H-5′), 2.85 (ddd, J = 14.4,
8.3 and 5.3 Hz, 1 H, H-2′β), 1.92 [d, J = 1.0 Hz, 3 H, CH3-C(5)],
1.83 (dd, J = 14.4 and 1.8 Hz,
1 H, H-2’α), 1.5-2.1 (m, 6 H, H-6′,
H-7′,
H-8′), 0.97 (m, 18 H, CH
3
CH2Si),
0.62 (m, 12 H, CH3
CH
2
Si). The configuration of C-1′ was
established by NOE: Both H-1′ and H-3′ show a
strong NOE with H-2′β. No NOE was observed between
H-3′ and H-6. Furthermore, a strong NOE was observed between
H-3′ and H-5′ proving the configuration of C-3′ and
C-5′ given in Scheme
[4]
. 13C NMR
(125 MHz, CDCl3, as obtained from the HSQC and HMBC spectra): δ = 163.7
(C-4), 150.3 (C-2), 137.6 (C-6), 109.7 (C-5), 97.8 (C-4′),
85.5 (C-1′), 78.3 (C-5′), 75.6 (C-3′), 42.9
(C-2′), 31.9 and 29.4 (C-8′ and C-6′),
17.9 (C-7′), 12.4 (CH3-C-5), 6.7 (CH
3
CH2Si),
4.9 (CH3
CH
2
Si). ESI-MS: 511 (M + H+);
509 (M - H+).
1β: 1H
NMR (500 MHz, CDCl3): δ = 8.01 (b,
1 H, NH), 8.00 (q, J = 1.0 Hz,
1 H, H-6), 6.28 (dd, J = 7.8
and 5.5 Hz, 1 H, H-1′), 4.23 (dd, J = 5.6
and 3.0 Hz, 1 H, H-3′), 3.91 (dd, J = 9.5
and 8.3 Hz, 1 H, H-5′), 2.25 (ddd, J = 12.9,
5.5 and 3.0 Hz, 1 H, H-2′α), 2.11 (ddd, J = 12.9, 7.8 and 5.6 Hz, 1
H,
H-2′β), 1.94 [d, J = 1.0 Hz, 3 H, CH3-C(5)],
1.5-2.1 (m, 6 H, H-6′, H-7′, H-8′),
0.97 (m, 18 H, CH
3
CH2Si),
0.62 (m, 12 H, CH3
CH
2
Si). The configuration of C-1′ was
established by NOE: H-1′ shows a strong NOE with H-2′α,
and H-3′ a strong NOE with H-2′β. A weak
NOE was observed between H-3′ and H-6. Furthermore, a strong
NOE was observed between H-3′ and H-5′ proving
the configuration of C-3′ and C-5′ given in Scheme
[4]
. 13C
NMR (125 MHz, CDCl3, as obtained from the HSQC and HMBC
spectra):
δ = 163.7 (C-4), 150.3 (C-2),
136.6 (C-6), 109.7 (C-5), 95.7 (C-4′), 84.4 (C-1′),
76.9 (C-5′), 74.4 (C-3′), 41.8 (C-2′),
31.4 and 29.2 (C-8′ and C-6′), 17.8 (C-7′),
12.4 (CH
3
-C-5),
6.7 (CH
3
CH2Si),
4.9 (CH3
CH
2
Si). ESI-MS: 511(M + H+);
509 (M - H+).
<A NAME="RG13302ST-17">17</A>
Hehre WJ.
Yu J.
Klunzinger PE.
Lou L.
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<A NAME="RG13302ST-18">18</A>
Grzeskowiak K.
Yanagi K.
Prive GG.
Dickerson RE.
J. Biol. Chem.
1991,
266:
8861