J.E. Nidhiry, K.R. Prasad / Tetrahedron 69 (2013) 5525e5536
5535
121.0, 118.9, 117.9, 110.5, 108.2, 97.4, 74.5, 61.6, 55.6, 55.2, 53.0, 42.3,
39.1, 32.8, 30.4, 23.8, 21.7, 8.0; HRMS: [MþH] found 343.2384.
C21H30N2O2þH requires 343.2386.
(6:4) as eluent to afford 3 (0.004 g, 22%) as a white solid. Rf 0.60 (40%
EtOAc/petroleum ether); [
a
]
D
24 ꢀ93.0 (c 0.1, CHCl3), [lit:9d
[
a
]
24 ꢀ99.0
D
(c 0.27, CHCl3)]; mp (139e142 ꢁC), [lit:9d mp (144e146 ꢁC)]; IR (KBr):
nmax 3426, 2925, 1629, 1245 cmꢀ1 1H NMR (400 MHz, CDCl3): dH
;
4.1.21. ((2R,13bS)-2-Ethyl-2,3,4,5,7,8,13,13b-octahydro-1H-azepino
7.72 (br s,1H), 7.48 (d, J¼6.8 Hz,1H), 7.28 (d, J¼7.1 Hz,1H), 7.14e7.01
(m, 2H), 3.25 (d, J¼11.9 Hz,1H), 2.92 (dd, J1¼11.5, J2¼4.5 Hz,1H), 2.86
(dd, J1¼4.3, J2¼2.8 Hz, 1H), 2.79e2.63 (m, 2H), 2.51e2.39 (m, 1H),
2.42 (dd, J1¼4.4, J2¼2.8 Hz,1H), 2.33 (td, J1¼11.5, J2¼4.5 Hz,1H), 2.25
(td, J1¼11.5, J2¼3.2 Hz,1H),1.93 (dd, J1¼13.7, J2¼7.7 Hz,1H),1.67e1.51
(m, 2H), 1.54 and 1.46 (ABq, J1¼J2¼19.3 Hz, 2H), 1.31e1.17 (m, 2H),
1.21e1.06 (m, 2H), 0.85 (t, J¼7.5 Hz, 3H); 13C NMR (100 MHz, CDCl3):
dC 139.9, 134.8, 128.9, 120.1, 118.6, 117.4, 110.0, 108.7, 56.7, 55.1, 53.2,
37.1, 34.7, 33.4, 32.0, 22.7, 22.4, 22.0, 7.8; HRMS: [MþH] found
283.2175. C19H26N2þH requires 283.2174.
[10,20:1,2]pyrido[3,4-b]indol-2-yl)methanol (29
a
) and ((2R,13bR)-2-
ethyl-2,3,4,5,7,8,13,13b-octahydro-1H-azepino[10,20:1,2]pyrido[3,4-b]
indol-2-yl)methanol (29 ). The following procedure for 29 is
representative. To a stirred solution of the eMOM ether 34
b
a
a
(0.023 g, 0.07 mmol) in MeOH (1.5 mL) was added 6 N HCl (1.5 mL)
at 0 ꢁC. The reaction mixture was then warmed up to room tem-
perature and stirred for 3 h at room temperature. After completion
of the reaction (TLC), it was quenched by addition of solid NaHCO3
and filtered through a short pad of Celite and the Celite pad was
washed with EtOAc (10 mL). The solvent was evaporated off and the
crude residue thus obtained was purified by column chromatog-
raphy on deactivated neutral alumina using EtOAc/MeOH (8:2) as
Acknowledgements
eluent to afford 29
Compound 29 : Rf 0.40 (20% MeOH/EtOAc); [
CHCl3); IR (neat): nmax 3291, 2926, 2855, 1462 cmꢀ1
a (0.012 g, 60%) as a yellow oil.
We thank the Department of Science and Technology (DST),
New Delhi for funding. K.R.P. is a Swarnajayanthi fellow of DST, New
Delhi. J.E.N. thanks Council of Scientific and Industrial Research
(CSIR), New Delhi for a senior research fellowship.
24
a
a
]
þ40.1 (c 0.7,
D
;
1H NMR
(400 MHz, CDCl3): dH 8.22 (br s, 1H), 7.47 (d, J¼7.5 Hz, 1H), 7.29 (d,
J¼7.7 Hz, 1H), 7.19e7.03 (m, 2H), 3.99 (d, J¼8.5 Hz, 1H), 3.60 (s, 2H),
3.21e2.53 (m, 6H), 2.11 (dd, J1¼14.0, J2¼2.4 Hz, 1H), 1.93e1.76 (m,
2H), 1. 76 (dd, J1¼15.0, J2¼9.3 Hz, 1H), 1.55e1.40 (m, 2H), 1.32 (q,
J¼7.5 Hz, 2H), 0.87 (t, J¼7.5 Hz, 3H); 13C NMR (100 MHz, CDCl3): dC
136.1, 135.9, 127.0, 121.3, 119.2, 118.0, 110.7, 108.1, 68.4, 56.2, 54.7,
52.1, 40.5, 40.2, 34.8, 32.4, 25.3, 20.2, 8.0; HRMS: [MþH] found
299.2127. C19H26N2OþH requires 299.2123.
Supplementary data
Supplementary data related to this article can be found online at
References and notes
Compound 29b: white solid; yield: 57%. Rf 0.40 (20% MeOH/
24
EtOAc); [
a
]
ꢀ63.0 (c 0.3, CHCl3); mp 191e192 ꢁC, [lit:8j mp
D
1. (a) Zenk, M. H.; Juenger, M. Phytochemistry 2007, 68, 2757; (b) Leonard, J. Nat.
Prod. Rep. 1999, 16, 319; (c) Saxton, J. E. Nat. Prod. Rep. 1997, 14, 559.
230e232 ꢁC]; IR (KBr): nmax 3432, 2924, 2855, 1458 cmꢀ1; 1H NMR
(400 MHz, CDCl3): dH 7.61 (br s, 1H), 7.47 (d, J¼7.6 Hz, 1H), 7.30 (d,
J¼7.6 Hz, 1H), 7.19e7.04 (m, 2H), 3.75 (d, J¼8.0 Hz, 1H), 3.39 and
3.36 (ABq, J1¼J2¼10.8 Hz, 2H), 3.14 (dd, J1¼9.4, J2¼5.0 Hz, 2H),
3.02e2.84 (m, 1H), 2.78e2.61 (m, 2H), 2.55 (td, J1¼10.6, J2¼2.3 Hz,
1H), 2.05e1.85 (m, 2H), 1.85 (dd, J1¼15.1, J2¼8.6 Hz, 1H), 1.80e1.58
(m, 2H), 1.54 (qd, J1¼7.5, J2¼3.2 Hz, 2H), 1.58e1.38 (m, 1H), 0.95 (t,
J¼7.5 Hz, 3H); 13C NMR (100 MHz, CDCl3): dC 136.2, 136.0, 127.1,
121.4, 119.4, 118.0, 110.7, 109.0, 68.6, 60.1, 56.4, 53.4, 42.1, 40.1, 34.5,
30.3, 25.0, 21.2, 8.2; HRMS: [MþH] found 299.2125. C19H26N2OþH
requires 299.2123.
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methanesulfonyl chloride (0.04 mL) at 0 ꢁC under nitrogen atmo-
sphere and the reaction mixture was stirred at the same temper-
ature for 4 h. After completion of the reaction (TLC), evaporated
excess methanesulfonyl chloride and pyridine were removed at
room temperature. The resulting residue was washed with diethyl
ether (2ꢂ2 mL), treated with water (0.2 mL) and 10% NH4OH
(0.4 mL) with cooling at 0 ꢁC and extracted with CHCl3 (2ꢂ10 mL).
The combined organic layers were dried over anhydrous Na2SO4.
Evaporation of the solvent in vacuo afforded a gummy residue,
which was dissolved in dry CHCl3 (1.5 mL) and refluxed under N2
atmosphere for 3 h. Evaporation of the solvent in vacuo afforded
the quaternary salt as a yellow hygroscopic solid.
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absolute EtOH (1 mL). After transferring liquid NH3 (5 mL) into the
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persisted for 20 min. The reaction was quenched by the addition of
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ꢁ
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