Asymmetric total synthesis of D-myo-inositol 1,2,4,5-tetrakisphosphate and its P-2-(O-aminopropyl) derivative

Full text of DOI:10.1021/jo951057k

J . Org. Chem. 1996, 61, 393-397
393
methyl R-D-glucopyranoside (1) provides R-D-glucopyran-
oside 2.18 Selective monobenzylation (37% isolated yield)
of the C-2 hydroxyl19 and then p-methoxybenzylation
(PMB) of the remaining hydroxyl group (75% yield) gave
the fully protected ether 4. Regioselective ring opening
of the p-methoxybenzylidene acetal using DIBAL-H at
-40 °C then gave compound 5 in 77% yield with >90%
regioselectivity.20 Swern oxidation21 of the alcohol gave
an aldehyde (>90% hydrated), which was converted
(Ac2O, CH3CN, K2CO3)22 in 79% yield directly to the
2-enol acetate 6. Ferrier rearrangement17 of 6 using
mercuric acetate, followed by treatment with aqueous
sodium chloride resulted in the desired axial 2-hydroxyl
stereochemistry in 59% yield. Stereoselective reduction
of the carbonyl group with sodium triacetoxyborohy-
dride23 provided the myo-inositol skeleton 8 in 55% yield.
Basic hydrolysis provided the triol 9 (90%), which was
converted (2,2-dimethoxypropane, TsOH) into the ther-
modynamically stable24 ketal 10 as the main isomer (85%
yield). Benzylation of the remaining free hydroxyl group
in the presence of NaH and benzyl bromide in DMF
offered the fully protected ether 11 in 80% yield. Re-
moval of the isopropylidene group under very mild
conditions (catalytic amount of p-TsOH acid in aqueous
acetone) at rt for 48 h gave the 1,2-diol in 77% yield.24
The structure of diol 12 was confirmed by comparison of
the proton NMR spectra and melting point and mixed
melting point with its racemic form25 synthesized from
1,2:4,5-bis-O-isopropylidene-myo-inositol by a known
route.24 Stannylation26 of two adjacent hydroxyls in the
presence of Bu4NI in toluene followed by p-methoxyben-
zylation resulted in 1,4,5-tri-O-p-methoxybenzyl-3,6-di-
O-benzyl-myo-inositol (13) with the 2-hydroxyl unpro-
tected to allow access to the enantiomerically pure P-2-
modified Ins(1,2,4,5)P4 analogue.
Asym m etr ic Tota l Syn th esis of
D-m yo-In ositol 1,2,4,5-Tetr a k isp h osp h a te
a n d Its P -2-(O-Am in op r op yl) Der iva tive
J ian Chen, Gyo¨rgy Dorma´n, and Glenn D. Prestwich*
Department of Chemistry, University at Stony Brook,
Stony Brook, New York 11794-3400
Received J une 12, 1995
The second messenger D-myo-inositol 1,4,5-trisphos-
phate (Ins(1,4,5)P3 or IP3) interacts stereospecifically with
membrane receptors (IP3R) to promote the release of Ca2+
from intracellular stores.1-3 Receptor proteins that
recognize IP3 and mediate its role in calcium mobilization
have been characterized and purified.4-6 Considerable
effort has been invested in defining the affinity of various
IP3R subtypes and of IP3 analogues.7-15 Recently, an IP3-
gated calcium channel protein from rat olfactory cilia was
found to respond to a 100-fold lower concentration of
Ins(2,4,5)-IP3 relative to Ins(1,4,5)P3.16 Moreover, affinity
probes based on P-1-tethered IP3 showed only very
modest utility in characterizing these unique vertebrate
olfactory IP3Rs (D. L. Kalinoski, D. Restrepo, and G. D.
Prestwich, unpublished results). Thus, we devised a
hybrid ligand possessing both Ins(1,4,5)P3 and Ins(2,4,5)P3
recognition elements. A new affinity probe was also
prepared in which the tethering group was attached via
a phosphodiester linkage from the P-2 phosphate moiety.
We now describe the synthesis of optically-active D-myo-
Ins(1,2,4,5)P4 and its P-2-(O-aminopropyl)phosphodiester
derivatives.
The synthesis of 2-O-(3-aminopropyl)Ins(1,2,4,5)P4 (17)
uses a modification11 of the Ferrier rearrangement17 to
establish the optically-pure D-myo-inositol skeleton. The
synthetic strategy is summarized in Scheme 1. Thus,
selective protection of C-4 and C-6 hydroxyls of the
Phosphitylation of the hydroxy group of 13 with
benzyloxy 3-(N-carboxyamino)propyl diisopropylamino
phosphite13 in the presence of 1H-tetrazole and followed
by m-CPBA oxidation gave the fully protected amino-
propyl-tethered inositol 14 in 87% yield. Although DDQ25
was unable to remove the three PMB groups, ceric
ammonium nitrate27 in acetonitrile/water (9:1) gave the
triol 15 in 43% yield. Phosphitylation and oxidation of
the triol 15 described for 14 gave the fully protected
derivative 16 (76% yield). Hydrogenolysis removed the
benzyl groups to provide the optically-active, P-2-(O-
aminopropyl)-tethered D-myo-Ins(1,2,4,5)P4 derivative 17
in essentially quantitative yield after ion-exchange chro-
matography on Chelex (sodium form).13
(1) Berridge, M. J . Annu. Rev. Biochem. 1987, 56, 15-193.
(2) Berridge, M. J .; Irvine, R. F. Nature 1989, 341, 197-203.
(3) Berridge, M. J . Nature 1993, 361, 315-325.
(4) Ferris, C. D.; Huganir, R. L.; Supattapone, S.; Snyder, S. H.
Nature 1989, 342, 87-89.
(5) Chadwick, C. C.; Timerman, A. P.; Saito, A.; Mayrleitner, M.;
Schindler, H.; Fleischer, S. J . Biol. Chem. 1992, 267, 3473-3481.
(6) Supattapone, S.; Worley, P. F.; Baraban, J . M.; Snyder, S. H. J .
Biol. Chem. 1988, 263, 1530-1534.
(7) Hirata, M.; Watanabe, Y.; Ishimatsu, T., Ikebe, I.; Kimura, Y.;
Yamaguchi, K.; Ozaki, S.; Koga, T. J . Biol. Chem. 1989, 264, 20303-
20308.
(8) Hirata, M.; Narumoto, N.; Watanabe, Y.; Kanematsu, T.; Koga,
T.; Ozaki, S. Mol. Pharmacol. 1994, 45, 271-276.
(9) Beaucage, S. L.; Iyer, R. P. Tetrahedron 1993, 46, 10441-10488.
(10) Chaudhary, A.; Dorma´n, G.; Prestwich, G. D. Tetrahedron Lett.
1994, 35, 7521-7524.
(11) This modification has also been employed in the synthesis of
D-myo-P-1-(O-aminopropyl)-Ins(1,4,5)P3 (Dorma´n, G.; Chen, J .;
Prestwich, G. D. Tetrahedron Lett., in press), P-5-(O-aminopropyl)-
Ins(1,2,5,6)P4 (ref 10), and P-1-(O-aminopropyl)-Ins(1,3,4,5)P4 (ref 27).
(12) Prestwich, G. D.; Marecek, J . F. In Inositol Phosphates and
Related Compounds: Synthesis and Therapeutic Potential; Reitz, A.,
Ed.; ACS Symp. Series: Washington, DC, 1991; Vol. 463, pp 122-
131.
For biological comparisons, synthesis of untethered
optically-pure D-myo-1,2,4,5-IP4 was performed using the
(18) J ohansson, R.; Samuelsson, B. J . Chem. Soc., Perkin Trans. 1
1984, 2371-2374.
(19) Garegg, P. J .; Iversen, T.; Oscarson, S. Carbohydr. Res. 1976,
50, C12-C14.
(20) Mikami, T.; Asano, H.; Mitsunobu, O. Chem. Lett. 1987, 2033-
2036.
(13) Prestwich, G. D.; Marecek, J . F.; Mourey, R. J .; Theibert, A.
B.; Ferris, C. D.; Danoff, S. K.; Snyder, S. H. J . Am. Chem. Soc. 1991,
113, 1822-1825.
(21) Mancuso, A. J .; Swern, P. Synthesis 1981, 165-185.
(22) Cook, S. L.; Secrist, J . A., III. J . Am. Chem. Soc. 1979, 101,
1554-1564.
(14) (a) Mills, S. J .; Safrany, S. T.; Wilcox, R. A.; Nahorski, S. R.;
Potter, B. V. L. BioMed. Chem. Lett. 1993, 3, 1505-1510. (b) Kozikows-
ki, A. P.; Fauq, A. H.; Wilcox, R. A.; Nahorski, S. R. BioMed. Chem.
Lett. 1995, 5, 1295-1300.
(23) Evans, D. A.; Chopman, K. T.; Carreira, E. M. J . Am. Chem.
Soc. 1988, 110, 3560-3578.
(24) Gigg, J .; Gigg, R.; Payne, S.; Conant, R. J . Chem. Soc., Perkin
Trans. 1 1987, 423-429.
(25) Massy, D. J . R.; Wyss, P. Helv. Chim. Acta 1990, 73, 1037-
1057.
(26) Gigg, J .; Gigg, R.; Payne, S.; Conant, R. J . Chem. Soc., Perkin
Trans. 1 1987, 2411-2414.
(27) Estevez, V. A.; Prestwich, G. D. J . Am. Chem. Soc. 1991, 113,
9885-9887.
(15) Lu, P.-J .; Gou, D.-M.; Shieh, W.-R.; Chen, C.-S. Biochemistry
1994, 33, 11586-11597.
(16) Restrepo, D.; Teeter, J . H.; Honda, E.; Boyle, A. G.; Marecek,
J . F.; Prestwich, G. D.; Kalinoski, D. L. Am. J . Physiol. 1992, 263,
C667-C673.
(17) Ferrier, J . R.; Middleton, S. Chem. Rev. 1993, 93, 2779-2831.
0022-3263/96/1961-0393$12.00/0 © 1996 American Chemical Society

394 J . Org. Chem., Vol. 61, No. 1, 1996
Notes
Sch em e 1a
a
(a) 4-Methoxybenzaldehyde dimethyl acetal, p-TsOH, 50 °C, DMF, 2.5 h; (b) BnBr, CH2Cl2, n-Bu4NHSO4, 10% aqueous NaOH, reflux,
48 h; (c) NaH, PMB-Cl, DMF, 2 h; (d) DIBAL-H, CH2Cl2, -40 °C; (e) oxalyl chloride, DMSO, Et3N, CH2Cl2, -78 °C to rt; (f) Ac2O, K2CO3,
CH3CN, 80 °C, 8 h; (g) (1) Hg(OAc)2, 4:1 acetone:water, rt, 30 min, (2) saturated NaCl, rt, 24 h; (h) NaBH(OAc)3, HOAc, CH3CN, rt, 30
min; (i) NaOH, MeOH, reflux, 2 h; (j) 1% TsOH, 2,2-dimethoxypropane, acetone, rt, 72 h; (k) NaH, BnBr, DMF, rt, 1 h; (l) 1% TsOH,
acetone-water (50:1), rt, 48 h; (m) Bu2SnO, n-Bu4NI, toluene, reflux, 3 h, then PMB-Cl, 1.5 h; (n) (1) (BnO)P(N-i-Pr2)(OC3H6NHCbz),
1H-tetrazole, CH2Cl2, rt, (2) m-CPBA, -40 °C to rt, 1 h; (o) (NH4)2Ce(NO3)6, acetonitrile-water (9:1), 2 h; (p) (1) (BnO)2PN-i-Pr2, 1H-
tetrazole, CH2Cl2, rt, (2) m-CPBA, -40 °C to rt, 1 h; (q) 10% Pd-C, H2, 5 atm, 95% EtOH, rt, 6.5 h.
Sch em e 2a
a
(a) (1) (BnO)2PN-i-Pr2, 1H-tetrazole, CH2Cl2, rt, (2) m-CPBA, -40 °C to rt, 1 h; (b) (NH4)2Ce(NO3)6, acetonitrile-water (9:1), 2 h; (c)
(1) (BnO)2PN-i-Pr2, 1H-tetrazole, CH2Cl2, rt, (2) m-CPBA, -40 °C to rt, 1 h; (d) 10% Pd-C, H2, 5 atm, 95% EtOH, rt, 6.5 h.
intermediate compound 12 (Scheme 2). Phosphitylation
of the diol 12 under similar conditions gave the 1,2-
bisphosphate 18 in 80% yield. Removal of the two PMB
groups with (NH4)2Ce(NO3)6 resulted in free 4,5-hy-
droxyls 19 in 64% yield. Further phosphitylation gave
fully protected 1,2,4,5-tetrakisphosphate 20 in 90% yield.
Hydrogenolytic cleavage of all benzyl groups gave opti-
cally-pure myo-inositol 1,2,4,5-tetrakisphosphate 21 in
essentially quantitative yield. The racemic form of this
material has been previously show to have a high affinity
for the IP3 receptor14 and to mobilize Ca2+ in SH-SY5Y
cultured cells14 with approximately 2-3-fold lower po-
tency relative to Ins(1,4,5)P3. Biological tests of these
derivatives in olfactory IP3 receptor studies will be
reported in due course.
Exp er im en ta l Section
1H, 13C, and 31P NMR spectra were recorded in CDCl3 on a
QE-300 or AC-250 NMR spectrometer and are reported relative
to δ(TMS) ) 0 ppm. When necessary, solvents and reagents
were dried using standard procedures.
Meth yl 4,6-O-(p-m eth oxyben zylid en e)-r-D-glu cop yr a n o-
sid e (2) was prepared according to J ohansson et al.18 and
recrystallized from EtOAc; mp 197-198 °C.
Meth yl 2-O-Ben zyl-4,6-O-(p-m eth oxyben zylid en e)-r-D-
glu cop yr a n osid e (3). To a solution of methyl 4,6-O-(p-meth-
oxybenzylidene)-R-D-glucopyranoside (2, 26.5 g) in 2.65 L of
CH2Cl2 were added 10.6 g of tetra-n-butylammonium hydrogen
sulfate and 31.7 mL of benzyl bromide followed by 220 mL of
5% sodium hydroxide. The mixture was refluxed for 48 h. The
organic phase was separated, washed with water, dried (MgSO4),
and concentrated to a white syrup (120 g). After trituration with
hexane and EtOAc in hexane (2:1) to remove unreacted starting

Notes
J . Org. Chem., Vol. 61, No. 1, 1996 395
material, the crude product was purified on 1.5 kg of silica gel,
using a tert-butyl methyl ether-hexane eluent (1:1.5 to 1:1) to
give 15.7 g of pure and 9.0 g of partially purified benzyl ether 3
(yield 37%); mp 128-129 °C. 1H NMR (300 MHz, CDCl3) δ:
7.4-7.2 (m, 7H), 6.8 (d, 2H), 5.4 (s, 1H), 4.83-4.69 (m, 2H), 4.61
(d, J ) 3.6 Hz, 1H), 4.25 (dd, J ) 4.5, 9.8 Hz, 1H), 4.15 (t, J )
9.3 Hz, 1H), 3.83-3.73 (s+m, 4H), 3.71 (dd, J ) 10.2 Hz, 1H),
3.51-3.45 (m, 2H), 3.38 (s, 3H), 2.58 (bs, 1H) ppm. 13C NMR
(63 MHz, CDCl3) δ: 161.1, 137.3, 129.2, 128.8, 128.2, 127.7,
113.7, 101.9, 98.7, 81.2, 79.6, 76.5, 73.4, 70.3, 69.0, 62.0, 55.4
ppm.
Meth yl 2-O-Ben zyl-3-(p-m eth oxyben zyl)-4,6-O-(p-m eth -
oxyben zylid en e)-r-D-glu cop yr a n osid e (4). Methyl 3-O-ben-
zyl-4,6-O-(p-methoxybenzylidene)-R-D-glucopyranoside (3, 11 g,
27.2 mmol) in 100 mL of DMF was added to a suspension of
oil-free sodium hydride (2.127 g, 88.6 mmol, previously washed
three times with THF) in 15 mL of DMF followed by addition of
4-methoxybenzyl chloride (6.2 mL, 45.8 mmol) in 3 mL of DMF.
The mixture was stirred at 50 °C for 2 h. The usual workup (Rf
) 0.63, 50% EtOAc-hexane) gave 10.86 g (76%) of white solid
4; mp 144-146 °C. 1H NMR (250 MHz, CDCl3) δ: 7.43-7.25
(m, 9H), 6.90, 6.83 (2d, 4H), 5.50 (s, 1H), 4.87-4.63 (m, 4H),
4.58 (d, J ) 3.6 Hz, 1H), 4.23 (dd, J ) 4.3 Hz, 1H), 4.07 (t, 1H),
3.83-3.75 (s+m, 7H), 3.62-3.43 (m, 3H), 3.37 (s, 3H) ppm. 13C
NMR (63 MHz, CDCl3) δ: 162.0, 161.1, 137.7, 129.7, 128.4, 128.1,
127.9, 127.4, 113.7, 113.5, 101.2, 99.3, 82.1, 79.2, 78.3, 75.0, 73.7,
70.3, 69.0, 62.4, 55.2 ppm. Anal. Calcd for C30H34O8: C, 68.95;
H, 6.55. Found: C, 68.85; H, 6.19.
Meth yl 2-O-Ben zyl-3,4-d i-O-(p-m eth oxyben zyl)-r-D-glu -
cop yr a n osid e (5). To a solution of methyl 2-O-benzyl-3-(p-
m et h oxyben zyl)-4,6-O-(p-m et h oxyben zyliden e)-R-D-glu co-
pyranoside (4, 2.0 g, 3.83 mmol) in 30 mL of dry CH2Cl2 at -40
°C was added dropwise 1 M DIBAL-H (18 mL, 18 mmol) in
CH2Cl2. After stirring for 1 h, the reaction was quenched with
methanol. The mixture was kept at 0 °C, and a 0.5 M NaHSO4
solution was added dropwise to decompose the Al alkoxide
complex. The usual workup gave 1.54 g of methyl 2-O-benzyl-
3,4-di-O-(p-methoxybenzyl)-R-D-gluocopyranoside (5, 77% yield,
>90% selectivity). 1H NMR (250 MHz, CDCl3) δ: 7.35-7.20 (m,
9H), 6.88, 6.84 (2 × d, 4H), 4.92-4.63 (m, 4H), 4.55 (d, J ) 3.7
Hz, 1H), 3.97 (t, 1H), 3.79 (s, 6H), 3.72-3.63 (m, 3H), 3.5-3.35
(m, 2H), 3.35 (s, 3H) ppm. 13C NMR (63 MHz, CDCl3) δ: 158.6,
148, 131.0, 130.3, 129.7, 128.5, 128.1, 127.9, 113.9, 113.8, 98.2,
81.8, 80.0, 76.5, 75.4, 73.5, 70.7, 61.9, 55.3, 55.2 ppm. Anal.
Calcd for C30H36O8: C, 69.38; H, 6.76; O, 23.85. Found: C, 69.46;
H, 6.57; O, 23.66.
Meth yl (Z)-2-O-Ben zyl-3,4-d i-O-(p-m eth oxyben zyl)-6-O-
a cetyl-r-D-glu cos-5-en op yr a n osid e (6). To a solution of
oxalyl chloride (0.234 mL, 0.432 mmol) in 15 mL of CH2Cl2,
cooled to -78 °C, was added dropwise dry DMSO (0.38 mL, 0.86
mmol). The mixture was stirred at -78 °C for 10 min, and a
solution of methyl 2-O-benzyl-3,4-di-O-(p-methoxybenzyl)-R-D-
glucopyranoside (5, 568 mg, 1.08 mmol) in 5 mL of CH2Cl2 was
added over 10 min. The cloudy solution was stirred for 30 min,
then 1.2 mL of Et3N was added to produce a clear solution and
the mixture was warmed to rt. The usual workup gave an oil
used directly in the next step. The oil was dissolved in 13.5 mL
of dry CH3CN, and anhydrous K2CO3 (0.918 g, 6.7 mmol) was
added. After stirring for 10 min, acetic anhydride (0.6 mL, 6.3
mmol) was added and the mixture was refluxed overnight under
nitrogen. The volume was reduced to one-third, and the residue
was diluted with water and extracted with ether. The usual
workup gave 473 mg of 6 (79% for two steps) (Rf ) 0.33, 50%
EtOAc in hexane). 1H NMR (250 MHz, CDCl3) δ: 7.4-7.2 (m,
9H), 6.9, 6.5 (2s, 4H, PMB), 4.9-4.6 (m, 8H), 4.0-3.9 (m, 2H),
3.8 (s, 6H), 3.6-3.5 (m, 1H), 3.35 (s, 3H), 2.20 (s, 3H) ppm. 13C
NMR (63 MHz, CDCl3) δ: 167.3, 159.2, 153.3, 138.0, 135.1, 130.8,
129.8, 128.5, 128.1,123.0, 113.9, 113.8, 99.8, 81.1, 79.1, 75.4, 74.2,
73.7, 60.4, 56.2, 55.3 ppm. Anal. Calcd for C32H36O9: C, 68.73;
H, 6.29. Found: C, 68.66; H, 6.23.
EtOAc. Purification by flash chromatography (EtOAc in hexane
1:1.5) yielded 320 mg of 7 (59%). 1H NMR (250 MHz, CDCl3) δ:
7.33-7.13 (m, 9H), 6.86, 6.83 (2d, 4H, PMB), 5.16 (bs, 1H), 4.87-
4.70 (m, 5H), 4.46 (d, J ) 10.8 Hz, 1H), 4.32 (bs, 1H), 4.14-4.10
(m, 2H), 3.81, 3.80 (s,s, 6H), 3.85-3.80 (m, 1H), 2.52 (s, 1H),
2.20 (s, 3H) ppm. 13C NMR (63 MHz, CDCl3) δ: 195.0, 169.7,
159.0, 130.0, 129.7, 128.6, 128.0, 113.8, 83.2, 81.5, 78.9, 75.9,
74.9, 73.4, 73.2, 69.5, 55.3 ppm. FAB HRMS:
(MNa) calcd 573.2101, found 573.2124.
C31H34O9Na
1-O-Acetyl-3-O-ben zyl-4,5-d i-O-(p-m eth oxyben zyl)-m yo-
in ositol (8). To a solution of 1-O-acetyl-3-O-benzyl-4,5-di-O-
(p-methoxybenzyl)-2-deoxy-2-oxo-myo-inositol (7, 170 mg, 0.33
mmol) in 9.5 mL of dry acetonitrile were added sodium tri-
acetoxyborohydride (0.67 g, 3.1 mmol) and 1.6 mL glacial acetic
acid. The mixture was stirred for 45 min at rt, and the excess
sodium triacetoxyborohydride was destroyed by dropwise addi-
tion of 0.5 M NaHSO4. The mixture was extracted with EtOAc,
washed successively with 0.5 M NaHSO4 and saturated Na2HPO4,
dried (Na2SO4), and concentrated. The residue was recrystal-
lized from EtOAc-hexane to yield 100 mg of 8 (59%). 1H NMR
(250 MHz, CDCl3) δ: 7.32 (d, 4H), 7.26-7.23 (m, 5H), 6.86, 6.84
(d, d, 4H), 4.90-4.63 (m, 6H), 4.26 (bs, 1H), 4.06 (t, 1H), 3.92-
3.85 (m, 1H), 3.79 (s, 6H), 3.52 (m, 2H), 3.32 (t, 3H), 2.40 (s,
1H), 2.20 (s, 3H) ppm. 13C NMR (63 MHz, CDCl3) δ: 172.3,
158.7, 130.0, 129.6, 128.1, 128.0, 113.8, 113.6, 82.6, 80.6, 80.1,
75.5, 72.9, 67.1, 55.8 ppm. Anal. Calcd for C31H36O9: C, 67.37;
H, 6.57. Found: C, 67.23; H, 6.56.
3-O-Ben zyl-4,5-d i-O-(p-m eth oxyben zyl)-m yo-in ositol (9).
A mixture of 1-O-acetyl-3-O-benzyl-4,5-di-O-(p-methoxybenzyl)-
myo-inositol (8, 2.0 g, 3.62 mmol) and 40 mL of 0.35 M NaOH
in methanol was refluxed for 2 h. The usual workup gave 1.662
g of product 9 (90%); mp 144-146 °C. 1H NMR (250 MHz,
CDCl3) δ: 7.4-7.2 (m, 9H), 6.9-6.7 (m, 4H), 4.9 (m, 6H), 4.1
(m, 1H), 3.9 (m, 2H), 3.8 (2s, 6H), 3.4 (m, 2H), 3.2 (m, 1H), 2.6
(m, 1H), 2.5 (m, 2H) ppm. 13C NMR (CDCl3, 63 MHz) δ: 137.9,
130.9, 130.8, 129.6, 129.5, 128.5, 127.9, 113.9, 113.8, 82.5, 81.0,
80.1, 77.7, 77.1, 76.6, 75.4, 75.1, 72.6, 72.5, 71.8, 69.3, 55.3, 55.2
ppm. Anal. Calcd for C29H34O8: C, 68.22; H, 6.71. Found: C,
68.00, H, 6.68.
1,2-O-Isop r op ylid en e-3-O-b en zyl-4,5-d i-O-(p -m et h oxy-
ben zyl)-m yo-in ositol (10). A mixture of triol 9 (1.4 g, 2.745
mmol), 2,2-dimethoxypropane (1.4 g, 13.73 mmol), and 40 mg
of TsOH in 20 mL of dry acetone was stirred at rt. After 10
min, no starting material 9 was detected, and three spots
appeared in TLC. Stirring was continued for 2 days under the
same conditions. The usual workup gave 1.29 g of a colorless
oil in 85% yield (Rf ) 0.31, EtOAc-hexane 1:1). 1H NMR (300
MHz, CDCl3) δ: 7.4-7.2 (m, 9H), 6.9-6.7 (m, 4H), 4.9-4.6 (m,
6H), 4.3 (m, 1H), 4.1 (m, 1H), 3.9-3.8 (m, 3H), 3.8 (s, 6H, OMe),
3.2 (m, 1H), 2.4 (m, 1H), 1.48, 1.32 (2s, 6H) ppm. 13C NMR
(CDCl3, 63 MHz) δ: 129.7, 129.6, 128.5, 128.1, 127.9, 114.0,
113.9, 81.2, 78.2, 76.5, 74.7, 74.5, 74.2, 74.0, 73.3, 55.3, 27.9,
25.7 ppm. FAB HRMS:
found 573.2467.
C32H38O8Na (MNa) calcd 573.2464,
1,2-O-Isop r op ylid en e-3,6-d i-O-b en zyl-4,5-d i-O-(p -m et h -
oxyben zyl)-m yo-in ositol (11). 1,2-O-Isopropylidene-3-O-ben-
zyl-4,5-di-O-(p-methoxybenzyl)-myo-inositol (10, 1.29 g, 2.34
mmol) dissolved in 50 mL of DMF was added to a suspension of
oil-free sodium hydride (200 mg, 8.3 mmol) in 15 mL of DMF
followed by addition of benzyl bromide (1200 mg, 7.1 mmol) in
1.5 mL of DMF. The mixture was stirred at rt for 2 h. The
usual workup gave 1.2 g (yield 80%) of product 11 as a thick oil
(Rf ) 0.23, 25% EtOAc in hexane). 1H NMR (300 MHz, CDCl3)
δ: 7.4-7.2 (m, 14H), 6.85-6.75 (m, 4H), 4.9-4.6 (m, 8H), 4.2
(m, 1H), 4.1 (m, 1H), 3.9 (m, 2H), 3.76 (s, 6H, OMe), 3.65 (m,
1H), 3.36 (m, 1H), 2.4 (m, 1H), 1.48, 1.32 (2s, 6H) ppm. 13C NMR
(CDCl3, 63 MHz) δ: 130.0, 129.6, 128.6, 128.2, 127.9, 113.8,
113.6, 81.1, 79.6, 78.9, 77.5, 77.0, 76.8, 76.5, 74.4, 71.8, 71.7,
71.4, 55.3, 27.9, 27.0 ppm.
3,6-Di-O-b en zyl-4,5-d i-O-(p -m et h oxyb en zyl)-m yo-in osi-
tol (12). A mixture of 1,2-O-isopropylidene-3,6-di-O-benzyl-4,5-
di-O-(p-methoxybenzyl)-myo-inositol (11, 1.2 g, 1.87 mmol) and
40 mg of TsOH in 50 mL of acetone containing 0.5 mL of water
was stirred at rt until TLC showed no remaining starting
material (ca. 3 days). The usual workup gave the pure 12 (864
mg of solid, yield 77%), which was recrystallized from EtOAc
and hexane; mp 127-129 °C (lit.25 mp racemic form 130-131
°C). 1H NMR (300 MHz, CDCl3) δ: 7.4-7.2 (m, 14H), 6.9-6.7
1-O-Ace t yl-3-O-b e n zyl-4,5-d i-O-(p -m e t h oxyb e n zyl)-2-
d eoxy-2-oxo-m yo-in ositol (7). To a solution of methyl (Z)-2-
O-benzyl-3,4-di-O-(p-methoxybenzyl)-6-O-acetyl-R-D-glucos-5-
enopyranoside (6, 550 mg, 0.97 mmol) in 20 mL of acetone and
8 mL water was added mercuric acetate (3.10 g, 9.9 mmol). The
solution was stirred for 45 min and 12 mL of a saturated NaCl
solution was added. The mixture was stirred for 24 h. The
acetone was evaporated, and the residue was extracted with

396 J . Org. Chem., Vol. 61, No. 1, 1996
Notes
(m, 4H), 4.9-4.6 (m, 8H), 4.13 (m, 1H), 3.9 (m, 1H), 3.80 (m,
1H), 3.75 (s, 6H, OMe), 3.40 (m, 1H), 2.55 (s, 1H, OH), 2.45 (d,
1H, OH) ppm. 13C NMR (CDCl3, 63 MHz) δ: 129.6, 129.5, 128.6,
127.9, 113.8, 83.0, 81.3, 77.6, 77.1, 76.5, 75.6, 75.4, 72.6, 71.7,
69.2, 55.3 ppm. Anal. Calcd for C36H40O8: C, 71.98; H, 6.71.
Found: C, 71.79; H, 6.63.
248 mg, 0.165 mmol) was dissolved in 100 mL of 95% EtOH and
160 mg of 10% Pd-C was added. Hydrogenolysis at an initial
hydrogen pressure of ca. 5 atm was allowed to proceed at rt for
6.5 h. The catalyst was filtered off and washed with 30 mL of
2:1 ethanol-water followed by 3 mL of water. The filtrate was
brought to pH 8.0 with
a few drops of concd ammonium
hydroxide, and the solvent was removed in vacuo. The residue
was dissolved in 3 mL of water and applied to one 5 × 2 cm
column of Bio-Rad Chelex 100 resin (sodium form) eluted with
25 mL of water. Evaporation afforded 114 mg (95%) of the
sodium salt of 17 as a colorless glass. 1H NMR (300 MHz, D2O)
δ: 4.15-3.80 (m, 7H), 3.65 (d, J ) 9.6 Hz, 1H), 3.09 (t, J ) 6.9
Hz, 2H), 1.90-1.86 (m, 2H) ppm. 13C NMR (63 MHz, D2O) δ:
80.7, 78.4, 75.5, 75.1, 74.1, 67.0, 40.5, 40.1, 30.2 ppm. 31P NMR
(101 MHz, D2O) δ: 8.54, 8.08, 7.50, 3.65 (1:1:1:1) ppm. FAB
HRMS: C9H18NO18P4Na6 (MH+) calcd 689.8861, found 689.8894.
Tet r a b en zyl 1,2-(3,6-d i-O-b en zyl-4,5-d i-O-(p -m et h oxy-
ben zyl)-m yo-in osityl) Bisp h osp h a te (18). A solution of 3,6-
di-O-benzyl-4,5-di-O-(p-methoxybenzyl)-myo-inositol (12, 40 mg,
0.067 mmol) in 5 mL of CH2Cl2 and 1H-tetrazole (38 mg, 0.53
3,6-Di-O-ben zyl-1,4,5-tr i-O-(p-m eth oxyben zyl)-m yo-in osi-
tol (13). A mixture of 3,6-di-O-benzyl-4,5-di-O-(p-methoxyben-
zyl)-myo-inositol (12, 400 mg, 0.67 mmol), dibutyltin oxide (182
mg, 0.73 mmol), and Bu4NI (369 mg, 1 mmol) in 40 mL of toluene
was refluxed for 2 h. Then p-methoxybenzyl chloride (230 mg,
1.47 mmol) was added and the mixture was stirred for an
additional 2 h. The usual workup gave 400 mg of a solid (83%);
mp 122-124 °C. 1H NMR (300 MHz, CDCl3) δ: 7.4-7.2 (m,
16H), 6.9-6.7 (m, 6H), 4.9-4.6 (m, 10H), 4.3 (m, 1H), 4.15 (m,
1H), 3.9 (s, 9H, OMe), 3.40 (m, 1H), 2.50 (s, 1H, OH) ppm. 13C
NMR (CDCl3, 63 MHz) δ: 129.6, 128.6, 128.4, 127.9, 127.8, 127.7,
127.6, 113.8, 83.0, 81.3, 79.9, 79.5, 77.1, 75.9, 75.6, 72.8, 72.6,
72.4, 67.7, 55.3 ppm. Anal. Calcd for C44H48O9: C, 73.31; H,
6.72. Found: C, 73.23; H, 6.55.
mmol) was stirred at rt and
a solution of dibenzyl N,N-
Ben zyl N-Cbz-3-a m in o-1-p r op yl 2-[3,6-Di-O-ben zyl-1,4,5-
tr i-O-(p-m eth oxyben zyl)-m yo-in osityl] P h osp h a te (14). A
solution of 3,6-di-O-benzyl-1,4,5-tri-O-(p-methoxybenzyl)-myo-
inositol (13, 160 mg, 0.22 mmol) in 8 mL of CH2Cl2 and 1H-
tetrazole (62 mg, 0.88 mmol) was stirred at rt, while a solution
of benzyloxy N-Cbz-3-amino-1-propoxy N,N-diisopropylamino-
phosphite (198 mg, 0.44 mmol) in 2 mL of CH2Cl2was added.
The mixture was stirred at rt for 1 h and cooled to -40 °C,
m-CPBA (200 mg) was added, and the reaction was stirred for
30 min at 0 °C and then 30 min at rt. The mixture was diluted
with CH2Cl2, washed with 10% aqueous Na2SO3, saturated
NaHCO3, and water, dried (Na2SO4), concentrated, and chro-
matographed on silica gel using EtOAc-hexane-triethylamine
(20:20:1) (Rf ) 0.3) to give 210 mg (87%) of compound 14 as a
very viscous colorless oil. 1H NMR (250 MHz, CDCl3) δ: 7.4-
7.2 (m, 26H, phenyl), 6.9-6.7 (m, 6H, PMB), 5.2-4.6 (m, 16H),
4.1 (m, 2H), 3.9 (m, 2H), 3.85 (s, 9H, OMe), 3.5 (m, 2H), 3.2 (m,
2H), 1.8 (m, 2H) ppm. 13C NMR (63 MHz, CDCl3) δ: 159.3,
130.8, 130.2, 129.7, 129.6, 128.6, 128.5, 128.4, 128.1, 128.0; 127.9,
127.7, 113.9, 113.8, 82.9, 81.0; 78.6, 77.2, 76.7, 75.5, 72.4, 69.1,
66.6, 55.3, 37.2 ppm. 31P NMR (101 MHz, CDCl3): -0.52 ppm.
diisopropylphosphamide (92 mg, 0.27 mmol) in 1 mL of CH2Cl2
was added. The next procedure was the same as that for
compound 14. Purification by chromatography (70% EtOAc in
hexane, Rf ) 0.52) gave 60 mg (80%) of compound 18 as a syrup.
1H NMR (250 MHz, CDCl3) δ: 7.4-7.2 (m, 34H, phenyl), 6.85,
6.75 (AB, 4H, PMB), 5.3 (m, 1H), 5.1-4.4 (m, 19H), 3.95 (m,
1H), 3.8 (s, 6H), 3.5 (m, 1H) ppm. 13C NMR (63 MHz, CDCl3) δ:
129.6, 128.7, 128.6, 128.5, 128.4, 128.3, 128.2, 128.1, 127.9, 127.6,
113.8, 82.5, 80.4, 79.7, 78.6, 75.8, 75.5, 75.4, 72.7, 69.5, 69.4,
69.2, 69.1, 67.4, 55.3 ppm. 31P NMR (101 MHz, CDCl3) δ: 0.39,
-0.63 (1:1) ppm. FAB HRMS:
1121.4006, found 1121.4042.
C
64H67O14P2 (MH+) calcd
Tetr a ben zyl 1,2-(3,6-Di-O-ben zyl-m yo-in osityl) Bisp h o-
sp h a te (19). Tetrabenzyl 1,2-(3,6-di-O-benzyl-4,5-di-O-(p-meth-
oxybenzyl)-myo-inosityl) bisphosphate (18, 60 mg, 0.054 mmol)
was dissolved in 10 mL of CH3CN and water (9:1). After
addition of 3 equiv of (NH4)2Ce(NO3)6 (90 mg) in three portions,
the mixture was stirred at rt for 2 h. The workup as before (75%
EtOAc in hexane, Rf ) 0.33) gave 30 mg of compound 19 (64%).
1H NMR (300 MHz, CDCl3) δ: 7.4-7.05 (m, 30H, phenyl), 5.3
(d, J ) 10 Hz, 1H), 5.1-4.65 (m, 12H), 4.4 (d, J ) 11 Hz, 1H),
3.80-3.65 (m, 2H), 3.44 (m, 1H), 3.23 (d, J ) 11 Hz, 1H), 2.85
(s, 1H), 2.70 (s, 1H) ppm. 13C NMR (63 MHz, CDCl3) δ: 128.5,
128.4, 128.3, 128.2, 128.1, 127.9, 127.7, 127.6, 127.5, 79.5, 78.9,
FAB HRMS:
1104.4296.
C62H68NO14PNa (MNa) calcd 1104.4272, found
Ben zyl N-Cbz-3-a m in o-1-p r op yl 2-(3,6-Di-O-ben zyl-m yo-
in osityl) P h osp h a te (15). Benzyl N-Cbz-3-amino-1-propyl
2-[3,6-di-O-benzyl-1,4,5-tri-O-(p-methoxybenzyl)-myo-inosityl]
phosphate13 (14, 200 mg, 0.185 mmol) was dissolved in 50 mL
of acetonitrile and water (9:1). After addition of 3 equiv of
(NH4)2Ce(NO3)6 in three portions, the mixture was stirred at rt
for 2 h. After removal of acetonitrile, the residue was extracted
with ether. The usual workup gave 58 mg of compound 15 (43%)
(EtOAc in hexane 5:1, Rf ) 0.43). The 31P NMR spectra showed
two peaks (1:1) corresponding to two diastereoisomers. 1H NMR
(300 MHz, CDCl3) δ: 7.4-7.2 (m, 20H, phenyl), 5.4 (m, 1H), 5.1-
4.8 (m, 10H), 4.2 (m, 1H), 3.9 (m, 2H), 3.6 (m, 2H), 3.2 (m, 2H),
2.9 (m, 2H), 1.8 (m, 2H) ppm. 13C NMR (63 MHz, CDCl3) δ:
159.3, 128.5, 128.1, 127.9, 127.7, 81.6, 78.6, 77.6, 77.1, 76.6, 74.9,
66.5, 55.3, 37.2 ppm. 31P NMR (101 MHz, CDCl3) δ: 0.75, -1.08
(1:1) ppm. FAB MS: 653 (M+Na - Bn).
76.5, 75.3, 75.2, 74.3, 72.2, 71,89, 69.6, 69.5, 69.4, 69.3 ppm. 31
P
NMR (101 MHz, CDCl3) δ: 0.33, -0.51 (1:1) ppm. FAB HRMS:
C
48H51O12P2 (MH+) calcd 881.2856, found 881.2889.
Oct a b en zyl 1,2,4,5-(3,6-d i-O-b en zyl-m yo-in osit yl) Tet -
r a k isp h osp h a te (20). A solution of tetrabenzyl 1,2-(3,6-di-O-
benzyl-myo-inosityl) bisphosphate (19, 30 mg, 0.034 mmol) in 2
mL of CH2Cl2 and 1H-tetrazole (20 mg, 0.27 mmol) was stirred
at rt, and a solution of dibenzyl N,N-diisopropylphosphamide
(47 mg, 0.14 mmol) in 0.5 mL of CH2Cl2was added. The next
procedure was the same as that for compound 14. Purification
by chromatography (60% EtOAc in hexane, Rf ) 0.45) gave 45
mg (90%) of compound 20 as a syrup. 1H NMR (300 MHz,
CDCl3) δ: 7.4-6.9 (m, 30H, phenyl), 5.4 (d, J ) 9 Hz, 1H), 5.1-
4.7 (m, 24H), 4.6(m, 1H), 4.5 (t, J ) 10 Hz, 1H), 4.4 (t, J ) 10
Hz, 1H), 3.9 (t, J ) 9 Hz, 1H), 3.5 (d, J ) 9.6 Hz, 1H) ppm. 13C
NMR (63 MHz, CDCl3) δ: 128.8, 128.5, 128.3, 128.2, 128.1, 128.0,
127.9, 127.7, 127.6, 79.0, 78.9, 74.6, 72.2, 69.7, 69.6, 69.3 ppm.
31P NMR (101 MHz, CDCl3) δ: 0.27, -0.27, -0.63 (1:2:1) ppm.
Ben zyl N-Cbz-3-a m in o-1-p r op yl 2-(3,6-Di-O-ben zyl-1,4,5-
tr is(d iben zylp h osp h o)-m yo-in osityl) P h osp h a te (16).
A
solution of benzyl N-Cbz-3-amino-1-propyl 2-(3,6-di-O-benzyl-
myo-inosityl) phosphate (15, 210 mg, 0.293 mmol) in 8 mL of
CH2Cl2 and 1H-tetrazole (246 mg, 3.52 mmol) was stirred at rt
and a solution of dibenzyl N,N-diisopropylphosphamide (610 mg,
1.76 mmol) in 2 mL of CH2Cl2 was added. The next procedure
was the same as that for compound 14. Purification by chro-
matography (EtOAc-CH2Cl2 1:1, Rf ) 0.32) gave 309 mg (76%)
of compound 16 as a syrup. 1H NMR (300 MHz, CDCl3) δ: 7.4-
7.2 (m, 50H, phenyl), 5.4 (m, 1H), 5.1-4.5 (m, 23H), 4.2 (m, 1H),
3.4 (m, 2H), 3.2 (m, 2H), 1.8 (m, 2H) ppm. 13C NMR (63 MHz,
CDCl3) δ: 159.3, 128.5, 128.1, 127.0, 126.7, 81.6, 78.6, 77.6, 77.1,
76.6, 74.9, 66.5, 55.3, 37.2 ppm. 31P NMR (101 MHz, CDCl3) δ:
-0.04, -0.27, -0.53 (1:2:1) ppm. FAB HRMS: C80H83NO20P4-
Na (MNa) calcd 1524.4357, found 1524.4299.
FAB HRMS:
1401.4005.
C
76H77O18P4 (MH+) calcd 1401.4060, found
1,2,4,5-m yo-In ositol Tetr a k isp h osp h a te (21).14 Octaben-
zyl 1,2,4,5-(3,6-di-O-benzyl-myo-inosityl) tetrakisphosphate (20,
24 mg, 0.017 mmol) was dissolved in 25 mL of 95% EtOH, and
20 mg of 10% Pd-C was added. The next procedure was the
same as that for compound 17. Compound 21 (8 mg, yield 97%)
was obtained as a colorless glass after chromatography (3 × 2
cm column of Bio-Rad Chelex 100 resin, sodium form). 1H NMR
(300 MHz, D2O) δ: 4.2 (q, J ) 9 Hz, 1H), 4.0-3.8 (m, 4H), 3.6-
3.5 (m, 1H) ppm. 13C NMR (63 MHz, D2O) δ: 80.8, 79.9, 77.4,
77.1, 74.7, 73.7 ppm. 31P NMR (101 MHz, D2O) δ: 6.90, 5.88,
5.09 (2:1:1) ppm. FAB MS m/ z: 678 (M + 2), 630 (M - 2Na),
608 (M - 3Na + H), 586 (M - 4Na + 2H), 546 (M - 5Na + 3H),
542 (542 (M - 6Na + 4H).
2-O-(3-Am in op r op yl-1-p h osp h o)-m yo-in ositol 1,4,5-Tr is-
p h osp h a te (17). Benzyl N-Cbz-3-amino-1-propyl 2-(3,6-di-O-
benzyl-1,4,5-tris(dibenzylphospho)-myo-inosityl) phosphate (16,

Notes
Ack n ow led gm en t. We thank the NIH (Grant No.
NS 29632 to G.D.P.) for financial support and A.
Chaudhary, J . F. Marecek, J . D. Olszewski, and G. Du
for helpful discussions and critical reading of the
manuscript. D. L. Kalinoski and D. Restrepo (Monell
Chemical Senses Center, Philadelphia, PA) provided the
biological data which inspired this effort.
J . Org. Chem., Vol. 61, No. 1, 1996 397
Su p p or tin g In for m a tion Ava ila ble: 1H, 13C, and 31P
NMR spectra of compounds 3-21 (45 pages). This material
is contained in libraries on microfiche, immediately follows
this article in the microfilm version of the journal, and can be
ordered from the ACS; see any current masthead page for
ordering information.
J O951057K