References and Notes
<A NAME="RD36609ST-1A">1a</A>
Kobayashi S.
Tsuchiya K.
Harada T.
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<A NAME="RD36609ST-3">3</A> For a paper about chemical modifications
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Yasui K.
Tamura Y.
Nakatani T.
Horibe I.
Kawada K.
Koizumi K.
Suzuki R.
Ohtani M.
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For examples of the Prins cyclisation,
see:
<A NAME="RD36609ST-4A">4a</A>
Barry CStJ.
Crosby SR.
Harding JR.
Hughes RA.
King CD.
Parker GD.
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<A NAME="RD36609ST-4C">4c</A>
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<A NAME="RD36609ST-4F">4f</A>
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<A NAME="RD36609ST-4G">4g</A>
Marumoto S.
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2002,
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<A NAME="RD36609ST-4H">4h</A>
Kozmin SA.
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Kopecky DJ.
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<A NAME="RD36609ST-4K">4k</A>
Rychnovsky SD.
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<A NAME="RD36609ST-4L">4l</A>
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<A NAME="RD36609ST-4N">4n</A>
Yadav JS.
Reddy BVS.
Sekhar KC.
Gunasekar D.
Synthesis
2001,
885
<A NAME="RD36609ST-4O">4o</A>
Yadav JS.
Reddy BVS.
Reddy MS.
Niranjan N.
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<A NAME="RD36609ST-4P">4p</A>
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Niranjan N.
Prasad AR.
Eur.
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For our previous applications of
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Yadav JS.
Reddy MS.
Rao PP.
Prasad AR.
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Reddy MS.
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<A NAME="RD36609ST-5C">5c</A>
Yadav JS.
Reddy MS.
Prasad AR.
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<A NAME="RD36609ST-5D">5d</A>
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<A NAME="RD36609ST-5E">5e</A>
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Synlett
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2049
<A NAME="RD36609ST-5F">5f</A>
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Rao PP.
Reddy MS.
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<A NAME="RD36609ST-5G">5g</A>
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As shown below, compound 10 was subjected to TBS ether cleavage
and then transformed to the corresponding acetonide to confirm the anti relationship of hydroxyl groups by
examination of the ¹³C NMR spectrum.
See:
<A NAME="RD36609ST-6A">6a</A>
Rychnovsky SD.
Skalitzky DJ.
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1990,
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7099 ; One broad coupling (J = 9.0
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¹H
NMR supported the stereochemistry of the 4-α-methyl group
<A NAME="RD36609ST-7">7</A>
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<A NAME="RD36609ST-10B">10b</A>
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<A NAME="RD36609ST-10C">10c</A>
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<A NAME="RD36609ST-11">11</A>
Spectroscopic
and Physical Data of Selected Compounds(2
R
,3
S
,4
R
,6
R
)-2-[(
S
)-1-(Benzyloxy)propan-2-yl]-tetra-hydro-6-hydroxymethyl)-3-methyl-2
H
-pyran-4-ol
(5)
[α]D
²5 +18.5
(c 1.0, CHCl3); R
f
= 0.3
(SiO2, 60% EtOAc in hexane). IR (neat): 3390,
2926, 2859, 1359, 1158, cm-¹. ¹H NMR
(300 MHz, CDCl3): δ = 7.23-7.30
(m, 5 H), 4.39-4.55 (m, 2 H), 3.21-3.56 (m, 7
H), 2.02-2.11 (m, 1 H), 1.77-1.86 (m, 1 H), 1.22-1.44
(m, 2 H), 0.96 (d, 3 H, J = 6.64
Hz), 0.85 (d, 3 H, J = 6.64
Hz). ¹³C NMR (75 MHz, CDCl3): δ = 138.53,
128.30, 127.48, 79.47, 75.50, 73.33, 73.12, 72.97, 65.83, 40.40,
36.77, 34.10, 12.04, 9.54. ESI-HRMS: m/z
[M + Na]+ calcd
for C17H26NaO4: 317.1728; found: 317.1719.
(2
S
,3
R
,4
R
,5
R
)-1-(Benzyloxy)-5-(
tert
-butyldimethyl-silyloxy)-2,4-dimethyloct-7-en-3-ol
(10)
[α]D
²5 +13.9
(c 0.65, CHCl3); R
f
= 0.6
(SiO2, 10% EtOAc in hexane). IR (neat): 3500,
2930, 2855, 1461, 1063, 911 cm-¹. ¹H
NMR (300 MHz, CDCl3): δ = 7.30-7.27
(m, 5 H), 5.81-5.67 (m, 1 H), 5.08-4.49 (m, 2
H), 4.45-4.56 (m, 2 H), 3.97-3.92 (m, 1 H), 3.75
(d, 1 H, J = 9.82
Hz), 3.53-3.39 (m, 2 H), 2.37-2.20 (m, 2 H), 1.85-1.70
(m, 2 H), 1.46 (br, OH), 0.89-0.87 (m, 12 H), 0.75 (d,
3 H, J = 6.8
Hz), 0.06 (s, 3 H), 0.09 (s, 3 H). ¹³C
NMR (75 MHz, CDCl3): δ = 138.60, 135.13, 128.24,
127.47, 127.36, 116.90, 116.67, 81.09, 73.86, 72.82, 71.15, 60.70,
40.55, 39.38, 35.30, 26.02, 18.2, 9.7, 9.1,
-3.17, -4.37.
ESI-HRMS: m/z [M + Na]+calcd
for C23H40NaO3Si: 415.2644; found:
415.4635.
(3
E
,6
R
,7
S
,8
R
,9
S
,11
E
)-8-Methoxy-7,9-dimethyltridec-3,11-dien-6-ol
(4)
[α]D
²5 +4.0
(c 1.3, CHCl3); R
f
= 0.5
(SiO2, 20% EtOAc in hexane); IR (neat): 3420,
2966, 2931, 1715, 1457, 1083, 971 cm-¹; ¹H
NMR (300 MHz, CDCl3): δ = 5.62-5.29
(m, 4 H), 3.90-3.83 (m, 1 H), 3.48 (s, 3 H), 2.98 (m, 1
H), 2.57 (br, 1 H, OH), 2.27-1.75 (m, 8 H), 1.67 (d, 3
H, J = 6.40
Hz), 0.98 (t, 3 H, J = 7.34
Hz), 0.92 (d, 3 H, J = 7.9
Hz), 0.89 (d, 3 H, J = 7.8
Hz). ¹³C NMR (75 MHz, CDCl3): δ = 134.69,
129.18, 126.58, 125.63, 89.80, 70.6, 61.63, 38.10, 37.8, 37.2, 36.05, 25.63,
17.93, 14.57, 13.8, 10.91. ESI-HRMS: m/z [M + Na]+calcd
for C16H30NaO2: 277.1987; found:
277.1977.
(2
R
,3
S
,4
R
,6
R
)-3-Ethyl-tetrahydro-6-[(
E
,2
S
,3
R
,4
S
)-3-methoxy-4-methyloct-6-en-2-yl]-2-vinyl-2
H
-pyran-4-ol (3a)
[α]D
²5 -27.6
(c 0.65, CHCl3). IR (neat):
3427, 2967, 2929, 1718, 1457, 1089, 759 cm-¹. ¹H
NMR (300 MHz, CDCl3):
δ = 5.88-5.71
(m, 1 H), 5.49-5.36 (m, 2 H), 5.26-5.11 (m, 2 H),
3.69-3.45 (m, 3 H), 3.33 (s, 3 H), 3.05 (dd, 1 H, J = 9.55, 2.94
Hz), 2.32-2.27 (m, 1 H), 2.08-1.95 (m, 2 H), 1.76-1.41 (m,
7 H), 1.25-1.14 (m, 1 H), 1.02-0.75 (m, 11 H). ¹³C
NMR (75 MHz, CDCl3): δ = 130.65, 130.44,
128.71, 126.13, 84.8, 80.25, 74.34, 73.43, 70.67, 50.97, 49.21,
40.54, 38.99, 38.25, 35.49, 19.41, 17.96, 11.86, 10.18. ESI-HRMS: m/z [M + Na]+ calcd
for C19H34NaO3: 333.2405; found: 333.2409.
(4
R
,5
R
,7
R
,8
S
,9
R
,10
S
,12
E
)-4-Ethyl-9-methoxy-5-(methoxymethoxy)-8,10-dimethyltetradeca-2,12-dien-7-yl
acetate (17)
IR (neat): 2929, 2855, 1740, 1244, 1097,
966 cm-¹. ¹H NMR (300
MHz, CDCl3): δ = 5.51-5.03
(m, 5 H), 4.63-4.59 (m, 2 H), 3.56-3.41 (m, 1
H), 3.39 (s, 3 H), 3.37 (s, 3 H), 2.84-2.77 (m, 1 H), 2.03
(s, 3 H), 2.17-1.91 (m, 3 H), 1.66 (d, 6 H, J = 5.28 Hz),
1.75-1.50 (m, 4 H), 1.45-1.28 (m, 2 H), 0.92-0.79
(m, 9 H). ¹³C NMR (75 MHz, CDCl3): δ = 170.40, 134.51,
132.50, 125.50, 125.5, 96.30, 88.51, 66.99, 68.30, 58.0, 55.62,
49.06, 39.52, 36.42, 35.50, 33.75, 23.65, 21.20, 19.53, 19.35, 15.30,
12.42, 10.25. ESI-HRMS: m/z [M + Na]+ calcd
for C23H24NaO5: 421.2929; found:
421.2923.
(5
R
,6
R
)-5-Ethyl-5,6-dihydro-6-[(
E
,2
R
,3
S
,4
R
,5
S
)-2-hydroxy-4-methoxy-3,5-dimethylnon-7-enyl]pyran-2-one
(1)
[α]D
²5 -139.5
(c 0.35, CHCl3); R
f
= 0.3
(SiO2, 50% EtOAc in hexane); IR (neat): 3479,
2965, 2931, 1718, 1459, 1384, 1088 cm-¹. ¹H
NMR (300 MHz, CDCl3): δ = 7.04 (dd,
1 H, J = 9.82,
6.04 Hz), 6.04 (d, 1 H, J = 9.82
Hz), 5.50-5.32 (m, 2 H), 4.76 (m, 1 H), 4.23 (br d, 1 H),
3.47 (s, 3 H), 3.39 (br, OH), 2.36-2.27 (m, 1 H), 3.00-2.97
(m, 1 H), 2.13-2.06 (m, 1 H), 1.97-1.63 (m, 6
H), 1.67 (d, 3 H, J = 5.27
Hz), 1.56-1.45 (m, 1 H), 1.01 (t, 3 H, J = 7.18
Hz), 0.97 (d, 3 H, J = 7.18
Hz), 0.95 (d, 3 H, J = 6.70
Hz). ¹³C NMR (75 MHz, CDCl3): δ = 164.1,
144.8, 121.5, 96.1, 75.2, 69.7, 55.4, 41.8, 29.4, 20.1.164.75, 150.77,
130.08, 126.91, 120.72, 90.2, 77.73, 67.17, 61.55, 39.16, 39.05,
37.32, 36.73, 35.96, 20.76, 17.91, 15.1, 11.88, 10.96. ESI-HRMS: m/z [M + Na]+ calcd
for C19H32NaO4 347.2198; found:
347.2205.