Chiral cyclopentane-based mimics of D-myo-inositol 1,4,5-trisphosphate from D-glucose

Article abstract of DOI:10.1021/jo961158y

Two routes from D-glucose to chiral, ring-contracted analogs of the second messenger D-myo-inositol 1,4,5-trisphosphate are described. Methyl α-D-glucopyranoside was converted by an improved procedure into methyl 4,6-O-(p-methoxybenzylidene)-α-D-glucopyranoside (6) and thence into methyl 2-O-benzyl-3,4-bis-O-(p-methoxybenzyl)-α-D-gluco-hexodialdopyranoside (1,5) (14) in four steps. In the first ring-contraction method 14 was converted into methyl 2-O-benzyl-6,7-dideoxy-3,4-bis-O-(p-methoxybenzyl)-α-D-gluco-hept-6-e nopyranoside (1,5) (15), which on sequential treatment with Cp₂Zr(n-Bu)₂ followed by BF₃·Et₂O afforded a mixture of (1R,2S,3S,4R,5S)-3-(benzyloxy)-4-hydroxy-1,2-bis[(p-methoxybenzyl)oxy] -5-vinylcyclopentane (16) and its 4S,5R diastereoisomer 17. Removal of the p-methoxybenzyl groups of 16 and subsequent phosphorylation and deprotection afforded the first target compound, (1R,2R,3S,4R,5S)-3-hydroxy-1,2,4-tris(phosphonooxy)-5-vinylcyclopentan e (3). In the second route, intermediate 14 was subjected to SmI₂-mediated ring contraction to give (1R,2S,3S,4R,5S)-3-(benzyloxy)-4-hydroxy-5-(hydroxymethyl)-1,2-bis[(p- methoxybenzyl)oxy]cyclopentane (20). Benzylation of 20 provided (1R,2S,3S,4R,5S)-3-(benzyloxy)-6-[(benzyloxy)methyl]-4-hydroxy-1,2-bis [(p-methoxybenzyl)oxy]cyclopentane (22) and (1R,2S,3S,4R,5S)-3,4-bis(benzyloxy)-5-(hydroxymethyl)-1,2-bis[(p-metho xybenzyl)oxy]cyclopentane (21), which were elaborated to the target trisphosphates (1R,2R,3S,4R,5S)-3-hydroxy-5-(hydroxymethyl)-1,2,4-tris(phosphonooxy)c yclopentane (4) and (1R,2S,3R,4R,5S)-1,2-dihydroxy-3,4-bis(phosphonooxy)-5-[(phosphonooxy) methyl]cyclopentane (5), respectively. Both 3 and 4 mobilized intracellular Ca²⁺, but 4 was only a few fold less potent than D-myo-inositol 1,4,5-trisphosphate, demonstrating that effective mimics can be designed that do not bear a six-membered ring.

Full text of DOI:10.1021/jo961158y

J . Org. Chem. 1996, 61, 7719-7726
7719
Ch ir a l Cyclop en ta n e-Ba sed Mim ics of D-m yo-In ositol
1,4,5-Tr isp h osp h a te fr om D-Glu cose
David J . J enkins, Andrew M. Riley, and Barry V. L. Potter*
Department of Medicinal Chemistry, School of Pharmacy & Pharmacology, University of Bath,
Claverton Down, Bath BA2 7AY, Somerset, U.K.
Received J une 19, 1996X
Two routes from D-glucose to chiral, ring-contracted analogs of the second messenger D-myo-inositol
1,4,5-trisphosphate are described. Methyl R-D-glucopyranoside was converted by an improved
procedure into methyl 4,6-O-(p-methoxybenzylidene)-R-D-glucopyranoside (6) and thence into methyl
2-O-benzyl-3,4-bis-O-(p-methoxybenzyl)-R-D-gluco-hexodialdopyranoside (1,5) (14) in four steps. In
the first ring-contraction method 14 was converted into methyl 2-O-benzyl-6,7-dideoxy-3,4-bis-O-
(p-methoxybenzyl)-R-D-gluco-hept-6-enopyranoside (1,5) (15), which on sequential treatment with
Cp2Zr(n-Bu)2 followed by BF3‚Et2O afforded a mixture of (1R,2S,3S,4R,5S)-3-(benzyloxy)-4-hydroxy-
1,2-bis[(p-methoxybenzyl)oxy]-5-vinylcyclopentane (16) and its 4S,5R diastereoisomer 17. Removal
of the p-methoxybenzyl groups of 16 and subsequent phosphorylation and deprotection afforded
the first target compound, (1R,2R,3S,4R,5S)-3-hydroxy-1,2,4-tris(phosphonooxy)-5-vinylcyclopentane
(3). In the second route, intermediate 14 was subjected to SmI2-mediated ring contraction to give
(1R,2S,3S,4R,5S)-3-(benzyloxy)-4-hydroxy-5-(hydroxymethyl)-1,2-bis[(p-methoxybenzyl)oxy]cyclo-
pentane (20). Benzylation of 20 provided (1R,2S,3S,4R,5S)-3-(benzyloxy)-6-[(benzyloxy)methyl]-
4-hydroxy-1,2-bis[(p-methoxybenzyl)oxy]cyclopentane (22) and (1R,2S,3S,4R,5S)-3,4-bis(benzyloxy)-
5-(hydroxymethyl)-1,2-bis[(p-methoxybenzyl)oxy]cyclopentane (21), which were elaborated to the
target trisphosphates (1R,2R,3S,4R,5S)-3-hydroxy-5-(hydroxymethyl)-1,2,4-tris(phosphonooxy)cyclo-
pentane (4) and (1R,2S,3R,4R,5S)-1,2-dihydroxy-3,4-bis(phosphonooxy)-5-[(phosphonooxy)methyl]-
cyclopentane (5), respectively. Both 3 and 4 mobilized intracellular Ca2+, but 4 was only a few
fold less potent than D-myo-inositol 1,4,5-trisphosphate, demonstrating that effective mimics can
be designed that do not bear a six-membered ring.
In tr od u ction
Many cell surface receptors on stimulation activate
phospholipase C, liberating the second messenger D-myo-
inositol 1,4,5-trisphosphate [Ins(1,4,5)P3, 1] (Figure 1).
Ins(1,4,5)P3 interacts with a family of intracellular recep-
tor-operated Ca2+ channels to mobilize non-mitochondrial
Ca2+ in many cell types,1 and extensive biological inves-
tigations have followed the discovery of this signaling
pathway in 1983.2 Additionally, the chemical synthesis
of structurally modified analogs of 1 has improved
understanding of its structure-activity profiles with
respect to its receptor and metabolizing enzymes.3 In
particular, a vicinal D-threo bisphosphate arrangement
is essential for Ca2+-releasing activity,3,4 while the third
phosphate and position 6 hydroxyl group provide en-
hanced affinity for the receptor.
Until recently, all reported approaches to structural
F igu r e 1. D-myo-Inositol 1,4,5-trisphosphate (1) and ring-
modification of Ins(1,4,5)P3 that produced agonists had
concentrated upon modifications at phosphorus or hy-
droxyl group deletion, reorientation, alkylation, or re-
placement with isosteres and other groups in the six-
membered cyclitol ring. The discovery of the naturally
occurring, potently agonistic adenophostins A and B,5
isolated from cultures of Penicillium brevicompactum,
contracted analogs.
has more recently stimulated rational design and syn-
thesis of Ins(1,4,5)P3 mimics based on D-glucose or
D-xylose.6 Nevertheless, the 3,4-bisphosphate/2-hydroxyl
arrangement, analogous to the 4,5-bisphosphate/6-hy-
droxyl triad in Ins(1,4,5)P3, is contained within the six-
membered pyranoside ring in all of these examples.
Therefore, the requirement of a six-membered ring for
activity has not been addressed. Since structure-activity
* To whom correspondence should be addressed. Tel.: 01225-826639.
Fax: 01225-826114. E-mail: B.V.L.Potter@bath.ac.uk.
X Abstract published in Advance ACS Abstracts, October 1, 1996.
(1) Berridge, M. J . Nature (London) 1993, 361, 315-325.
(2) Streb, H.; Irvine, R. F.; Berridge, M. J .; Schulz, I. Nature
(London) 1983, 306, 67-69.
(3) Potter, B. V. L.; Lampe, D. Angew. Chem., Int. Ed. Engl. 1995,
34, 1933-1972.
(4) Poirot, E.; Bourdon, H.; Chre´tien, F.; Chapleur, Y.; Berthon, B.;
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269, 369-372.
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1995, 1169-1170. Wilcox, R. A.; Erneux, C.; Primrose, W. U.; Gigg,
R.; Nahorski, S. R. Mol. Pharmacol. 1995, 47, 1204-1211. Hotoda, H.;
Takahashi, M.; Tanzawa, K.; Takahashi, S.; Kaneko, M. Tetrahedron
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S0022-3263(96)01158-9 CCC: $12.00 © 1996 American Chemical Society

7720 J . Org. Chem., Vol. 61, No. 22, 1996
J enkins et al.
Sch em e 1a
studies have demonstrated that positions 2 and 3, to
some extent, of Ins(1,4,5)P3 can be modified without
significant loss of activity,7 we reasoned that contracted
structures such as 2, in which the relative stereochem-
istry and substitution of positions equivalent to positions
4, 5, 6, and 1 of Ins(1,4,5)P3 are broadly retained, might
fulfill the recognition requirements of the Ins(1,4,5)P3
receptor. We report here the preparation of two such
compounds, (1R,2R,3S,4R,5S)-3-hydroxy-1,2,4-trisphos-
phono-5-vinylcyclopentane (3) and (1R,2R,3S,4R,5S)-3-
hydroxy-5-(hydroxymethyl)-1,2,4-trisphosphocyclopen-
tane (4), from D-glucose, using two recently described
carbohydrate ring-contraction methods,8,9 together with
a related derivative (1R,2S,3R,4R,5S)-1,2-dihydroxy-3,4-
bis(phosphonooxy)-5-[(phosphonooxy)methyl]cyclopen-
tane (5), in which the third phosphate has been relocated.
A preliminary account of the synthesis of 3 has ap-
peared.10
aReagents and conditions: (a) p-methoxybenzaldehyde dimethyl
acetal, p-toluenesulfonic acid, DMF, 70 °C, -MeOH; (b) (i)
n-Bu2SnO, n-Bu4NI, CH3CN, 4 Å molecular sieves, reflux; (ii)
BnBr, reflux; (c) NaH, PMBCl, DMF, rt; (d) LiAlH4, AlCl3, THF,
N2, reflux; (e) (i) DMSO, (COCl)2, CH2Cl2 then Et3N, -60 °C; (f)
BzCl, DMAP, pyridine; PMB ) p-methoxybenzyl, Bn ) benzyl;
Bz ) benzoyl.
Resu lts a n d Discu ssion
The known11 methyl 4,6-O-(p-methoxybenzylidene)-R-
D-glucopyranoside (6) was prepared on a 0.7 mol scale
by a slight modification of the literature method. Thus,
methanol liberated from the acid-catalyzed reaction of
methyl R-D-glucopyranoside with p-methoxybenzaldehyde
dimethyl acetal in DMF was removed via an air con-
denser. Subsequent removal of the solvent and recrys-
tallization afforded 6 in 84% yield without further
manipulation. Stannylene-mediated benzylation of 6
gave the monobenzyl ethers 7 and 8 in a ratio of 4.4:1,
and p-methoxybenzylation of the 2-benzyl derivative 7
under standard conditions provided fully protected 9
(Scheme 1).
Treatment of 9 with sodium cyanoborohydride and
trimethylsilyl chloride in acetonitrile gave the chromato-
graphically separable 10 and 11 in a ratio of ca. 1:1.7.
The structures of 10 and 11 were established by com-
parison of the chemical shifts of their position 6 carbon
atoms, as observed in the 13C NMR spectra in CDCl3. The
C-6 of 10 resonates at lower field (69.2 ppm) than that
of 11 (61.8 ppm) due to the R-effect of alkylation.12 These
assigned structures were confirmed by preparation of
benzoates 12 and 13. The 1H NMR spectrum of 12
displayed a deshielded triplet at 5.28 ppm, corresponding
to the position 4 methine; the position 6 methylene
protons of 13 were deshielded to 4.46-4.97 ppm. The
selectivity of p-methoxybenzylidene cleavage in this case
was much poorer than that reported for the correspond-
ing 2,3-di-O-benzyl glucoside;11 however, exclusive forma-
tion of 11 was observed on treatment of 9 with LiAlH4-
AlCl3 in refluxing THF.13
Aldehyde 14 was smoothly prepared by Swern oxida-
tion14 of 11. After column chromatography, the IR
spectrum indicated absorption at 3400-3650 cm-1, cor-
responding to OH stretching, in addition to the expected
absorption at 1745 cm-1, corresponding to CdO stretch-
ing. As azeotropic drying abolished the former band, it
was assumed to arise from hydration of the aldehyde
rather than from contamination by starting material.
Although sufficiently stable to allow characterization, 14
gradually rehydrated on standing in air for several days
and was therefore best prepared freshly. Hydration of
related aldehydes has been reported.15
Wittig methylenation of 14 provided vinyl carbohydrate
15 (Scheme 2). The zirconium-mediated ring-contraction
was carried out as described,8 by treating 15 with Cp2Zr-
(n-Bu)2 (prepared in situ from zirconocene dichloride and
2 equiv of n-butyllithium), followed by boron trifluoride
etherate in THF. A complication was the gradual loss
of p-methoxybenzyl protecting groups after the addition
of boron trifluoride etherate. Nevertheless, the desired
vinylcyclopentane 16 was obtained in 46% yield as a waxy
solid, together with a small amount of the kinetically
disfavored product 17, which was crystalline. The rela-
tive stereochemistry of substituents for each of 16 and
17 was confirmed by phase-sensitive 2D-NOESY and
NOE difference NMR spectroscopy, and the results of the
latter experiments are summarized in Figure 2.
(7) Marecek, J . F.; Prestwich, G. D. Tetrahedron Lett. 1989, 30,
5401-5404. Hirata, M.; Yanaga, F.; Koga, T.; Ogasawara, T.; Wa-
tanabe, Y.; Ozaki, S. J . Biol. Chem. 1990, 265, 8404-8407. Safrany,
S. T.; Wilcox, R. A.; Liu, C.; Potter, B. V. L.; Nahorski, S. R. Eur. J .
Pharmacol. (Mol. Pharmacol. Sect.) 1992, 226, 265-272. Wilcox, R.
A.; Nahorski, S. R.; Sawyer, D. A.; Liu, C.; Potter, B. V. L. Carbohydr.
Res. 1992, 234, 237-246. Wilcox, R. A.; Safrany, S. T.; Lampe, D.; Mills,
S. J .; Nahorski, S. R.; Potter, B. V. L. Eur. J . Biochem. 1994, 223, 115-
124. Kozikowski, A. P.; Ognyanov, V. I.; Fauq, A. H.; Wilcox, R. A.;
Nahorski, S. R. J . Chem. Soc., Chem. Commun. 1994, 599-600. Fauq,
A. H.; Kozikowski, A. P.; Ognyanov, V. I.; Wilcox, R. A.; Nahorski, S.
R. J . Chem. Soc., Chem. Commun. 1994, 1301-1302. Wilcox, R. A.;
Challiss, R. A. J .; Traynor, J . R.; Fauq, A. F.; Ognyanov, V. I.;
Kozikowski, A. P.; Nahorski, S. R. J . Biol. Chem. 1994, 269, 26815-
26821.
(8) Ito, H.; Motoki, Y.; Taguchi, T.; Hanzawa, Y. J . Am. Chem. Soc.
1993, 115, 8835-8836. Hanzawa, Y.; Ito, H.; Taguchi, T. Synlett 1995,
299-305.
(9) Che´nede´, A.; Pothier, P.; Sollogoub, M.; Fairbanks, A. J .; Sinay¨,
P. J . Chem. Soc., Chem. Commun. 1995, 1373-1374.
(10) Riley, A. M.; J enkins, D. J .; Potter, B. V. L. J . Am. Chem. Soc.
1995, 117, 3300-3301.
Acidic hydrolysis of the p-methoxybenzyl groups from
16 gave the triol 18. Phosphitylation using bis(benzyl-
oxy)(N,N-diisopropylamino)phosphine,16 followed by oxi-
dation of phosphites with m-CPBA, gave the fully pro-
tected trisphosphate 19. 31P NMR spectroscopy of the
(13) J oniak, D.; Kosˇ´ıkova´, B.; Kosa´kova´, L. Collect. Czech. Chem.
Commun. 1978, 43, 769-773.
(14) Omura, K.; Swern, D. Tetrahedron 1978, 34, 1651-1660.
(15) Estevez, V. A.; Prestwich, G. D. J . Am. Chem. Soc. 1991, 113,
9885-9887. Chaudhary, A.; Dorma´n, G.; Prestwich, G. D. Tetrahedron
Lett. 1994, 35, 7521-7524.
(11) J ohansson, R.; Samuelsson, B. J . Chem. Soc., Perkin Trans. 1
1984, 2371-2374.
(12) Ogawa, T.; Takahashi, Y.; Matsui, M. Carbohydr. Res. 1982,
102, 207-215.
(16) Yu, K.-L.; Fraser-Reid, B. Tetrahedron Lett. 1988, 29, 979-
982.

Mimics of D-myo-Inositol 1,4,5-Trisphosphate
J . Org. Chem., Vol. 61, No. 22, 1996 7721
Sch em e 2a
a
Reagents and conditions: (a) CH3PPh3, t-BuOK, THF; (b) “Cp2Zr”/THF then BF3‚Et2O, -78 °C to rt; (c) 1 M HCl/EtOH 1:2, reflux; (d)
(i) i-Pr2NP(OBn)2, 1H-tetrazole, CH2Cl2, (ii) m-CPBA, -78 °C; (e) Na/NH3, -78 °C; (f) SmI2, THF, HMPA, t-BuOH, rt; (g) NaH, BnBr,
DMF, 0 °C; (h) (i) OsO4, NaIO4, Et2O-H2O, rt, (ii) NaBH4, MeOH, rt; Bn ) benzyl, PMB ) p-methoxybenzyl.
rescence techniques and also using saponin-permeabi-
lized platelets loaded with 45Ca2+ 20
It was found to be a
.
full agonist, although with an EC50 value 65-fold higher
than that of Ins(1,4,5)P3. These results demonstrated for
the first time that myo-inositol 1,4,5-trisphosphate recep-
tor-mediated Ca2+ mobilization does not necessarily
require a cyclohexyl (or equivalent) structure.
At this stage it was impossible to say whether the
considerably reduced potency of 3 relative to Ins(1,4,5)P3
was related to the presence of the hydrophobic vinyl
group or was a necessary consequence of the reduced ring
size. In the five-membered ring, for example, the di-
hedral angle corresponding to O4-C4-C5-O5 of Ins-
(1,4,5)P3 is larger than in Ins(1,4,5)P3, and the relative
position of the third phosphate group is slightly altered.
However, noting that DL-3-O-ethyl-Ins(1,4,5)P3 and DL-
3-O-propyl-Ins(1,4,5)P321 both have EC50 values of greater
than 100 µM in SH-SY5Y neuroblastoma cells [cf.
Ins(1,4,5)P3 0.18 µM],22 it seemed likely that replacement
of the vinyl group of 3 with a more hydrophilic, hydroxyl-
containing side chain might increase its potency. An
obvious target was 4, in which the vinyl group is replaced
by hydroxymethyl, and a timely report by Sinay¨ and co-
workers9 offered a straightforward route from intermedi-
ate 14.
Thus, treatment of 14 with samarium (II) iodide in
THF in the presence of 2-methyl-2-propanol and HMPA
gave two products that were separated by column chro-
matography and identified as the reduced starting mate-
rial 11 (19%) and the derived 20 (37%). Benzylation of
20 at 0 °C with 1 equiv of NaH and 1.1 equiv of benzyl
bromide in dry DMF gave a mixture of 21 and 22 in a
ratio of 3:2, respectively. The structures of 21 and 22
were distinguished by comparison of chemical shifts of
the methylene carbon atoms of the C-5 side chain in the
F igu r e 2. Results of NOE difference spectroscopy of dia-
stereoisomers 16 and 17 (Bn ) benzyl, PMB ) p-methoxy-
benzyl). *Positive NOEs to H-3 and/or H-4 were observed for
17, but could not be quantified due to overlap of these signals
with one another and with OCH3 of PMB groups.
intermediate trisphosphite triester showed an unusually
5
high J PP coupling of 6.7 Hz [cf. 2.9 Hz and 3.4 Hz for
precursors of Ins(4,5)P217 and Ins(1,4,5)P318 respectively],
presumably reflecting the altered geometry of the P(III)-
P(III) interaction in a five-membered ring; similar values
were obtained for the other trisphosphites described in
this paper. Deprotection using sodium in liquid am-
monia19 removed the benzyl ether and six benzyl esters,
leaving the vinyl group intact. The logic of retaining this
unusual feature in the target molecule was to produce a
ring-contracted Ins(1,4,5)P3 analog containing the es-
sential recognition elements in the minimum number of
synthetic steps, but with the potential for further modi-
fication. Purification by ion-exchange chromatography
of the crude product on Q Sepharose fast flow resin gave
the target trisphosphate 3, which was isolated as the
triethylammonium salt and quantified by total phosphate
assay.19
Trisphosphate 3 was examined for Ca2+ mobilizing
activity at the platelet Ins(1,4,5)P3 receptor using fluo-
(17) Hamblin, M. R.; Potter, B. V. L.; Gigg, R. J . Chem. Soc., Chem.
Commun. 1987, 626-627.
(20) Murphy, C. T.; Elmore, M.; Kellie, S.; Westwick, J . Biochem.
J . 1991, 278, 255-261.
(21) Liu, C., Potter, B. V. L. Tetrahedron Lett. 1994, 35, 8457-8460.
(22) Wilcox, R. A.; Safrany, S. T.; Liu, C.; Nahorski, S. R.; Potter,
B. V. L. Unpublished results.
(18) Cooke, A. M.; Potter, B. V. L.; Gigg, R. Tetrahedron Lett. 1987,
28, 2305-2308.
(19) Sawyer, D. A.; Potter, B. V. L. J . Chem. Soc., Perkin Trans. 1
1992, 923-932.

7722 J . Org. Chem., Vol. 61, No. 22, 1996
J enkins et al.
for the first time that a six-membered ring is not an
absolute requirement for Ins(1,4,5)P3 receptor agonists.
A smaller ring polyphosphate that retained certain
structural elements of Ins(1,4,5)P3, namely three ap-
propriately oriented phosphates and an equivalent to the
6-hydroxyl group, could still be recognized by the recep-
tor. The enhanced potency of the hydroxymethyl analog
4 now shows that a cyclopentane-based structure can
possess Ca2+-mobilizing activity rivalling that of more
conventional Ins(1,4,5)P3 analogs based on six-membered
rings. The utility of ring-contraction methodologies for
the synthesis of other five-membered ring inositol phos-
phate analogs from carbohydrates is currently under
investigation, while the detailed biology of this new class
of second messenger mimics remains to be explored.
Exp er im en ta l Section
Ma ter ia ls a n d Meth od s. Chemicals were purchased from
Aldrich, Sigma, and Fluka. Dichloromethane was dried over
phosphorus pentoxide, distilled, and kept over 4 Å molecular
sieves. N,N-Dimethylformamide was distilled from barium
oxide under reduced pressure and then stored over 4 Å sieves.
Tetrahydrofuran (THF) was dried by passing through acti-
vated alumina to expel peroxide radicals, followed by distil-
lation from sodium in the presence of benzophenone ketyl.
2-Methyl-2-propanol was distilled from calcium hydride. Hexa-
methylphosphoric triamide (HMPA) was stored over 4 Å sieves.
Dimethyl sulfoxide (DMSO) and 1,4-dioxane were purchased
in anhydrous form.
TLC was performed on precoated plates (Merck TLC alu-
minum sheets silica F254, Art no. 5554) with detection by UV
light or with methanolic phosphomolybdic acid followed by
heating. Flash-column chromatography was performed on
silica gel (Sorbsil C60).25
For 31P NMR spectra δ values are denoted positive for shifts
downfield from external aqueous 85% phosphoric acid. FAB-
mass spectra were carried out using m-nitrobenzyl alcohol as
the matrix. Melting points (uncorrected) were determined
using a Kofler block. Optical rotations were measured at
ambient temperature. Ion-exchange chromatography was
performed on an LKB-Pharmacia medium pressure ion ex-
change chromatograph using DEAE Sepharose or Q Sepharose
fast flow by elution with a gradient of triethylammonium
hydrogencarbonate (TEAB) buffer. Quantitative analysis of
phosphate was performed using a modification of the Briggs
phosphate assay.19,26
(N,N-Diisopropylamino)dichlorophosphine was prepared by
the method of Tanaka et al.27 by adding 2 equiv of diisopro-
pylamine to a solution of PCl3 in dry ether at -78 °C. The
crude product (δP 166.4) was purified by distillation under
reduced pressure, and reaction with 2 equiv of benzyl alcohol
in the presence of 2 equiv of triethylamine afforded bis-
(benzyloxy)(N,N-diisopropylamino)phosphine28 (δP 145.24), which
was purified by flash chromatography.
F igu r e 3. Energy-minimized structures of Ins(1,4,5)P3 and
ring-contracted analog 4.
13C NMR spectra, the R-effect of alkylation causing this
signal in the spectrum of 22 to be deshielded relative to
that of 21.
Benzylation of the major product 16 of the zirconium-
mediated contraction gave 23, which on sequential treat-
23
ment with OsO4-NaIO4 followed by NaBH4 also af-
forded 21, thereby confirming the stereochemistry of 20
and derivatives.
Diastereoisomers 21 and 22 were individually hydro-
lyzed to triols 24 and 25, respectively. These were
phosphitylated and oxidized to 26 and 27, respectively,
and deprotected to the target trisphosphates 5 and 4,
respectively, as described for precursors of 3. Both 4 and
5 were purified by ion-exchange chromatography and
isolated as their triethylammonium salts.
Trisphosphates 4 and 5 were examined for Ca2+
mobilizing activity in permeabilized J urkat T-lympho-
cytes.24 Preliminary results demonstrated an EC50 value
for 4 only 2-4-fold higher than that of Ins(1,4,5)P3 itself,
showing that replacement of the hydrophobic vinyl sub-
stituent of 3 with hydroxymethyl results in a sharp
increase in potency. Energy-minimized structures of 4
and Ins(1,4,5)P3 (Figure 3) show clearly that the vicinal
phosphate groups and secondary hydroxyl of 4 are well-
placed to mimic the corresponding features in Ins-
(1,4,5)P3. It is not yet clear whether the enhanced
activity of 4 compared to 3 is due simply to the removal
of the hydrophobic vinyl group, or whether the primary
hydroxyl group engages in favorable interactions with the
Ins(1,4,5)P3 receptor binding site. Another possibility is
that the hydroxymethyl group influences the orientation
or ionization state of the adjacent phosphates by intra-
molecular hydrogen bonding. Interestingly, 5, in which
the relative arrangement of phosphate esters around the
ring is not conserved, released little Ca2+ at the concen-
trations tested. Full biological results will be published
elsewhere.
Molecular modeling calculations were performed on a Silicon
Graphics Indigo R3000 workstation using the Insight II (Ver.
2.3.5) and Discover (Ver. 2.9.5) molecular modeling packages
(Biosym Technologies, San Diego, USA). Energies were
calculated using the AMBER force field. Structures for 4 and
Ins(1,4,5)P3 were first energy-minimized by steepest descent,
and then partial charges were calculated for the fully-ionized
structures using the AM1 semiempirical method as imple-
mented in the MOPAC program (Ver. 6.0). The charged
structures were then reminimized and finally optimized using
the VAO9A minimizer.
In conclusion, the Ca2+-mobilizing ability of the pro-
totype ring-contracted Ins(1,4,5)P3 analog 3 demonstrated
(25) Still, W. C.; Kahn, M.; Mitra, A. J . Org. Chem. 1978, 43, 2923-
2925.
(26) Briggs, A. P. J . Biol. Chem. 1922, 53, 13-16.
(27) Tanaka, T.; Tamatsukuri, S.; Ikehara, M. Tetrahedron Lett.
1986, 27, 199-202.
(28) Bannwarth, W.; Trzeciak, A. Helv. Chim. Acta 1987, 70, 175-
186.
(23) Ferrier, R. J .; Stu¨tz, A. E. Carbohydr. Res. 1990, 205, 283-
291.
(24) Ward, S. G.; Lampe, D.; Liu, C.; Potter, B. V. L.; Westwick, J .
Eur. J . Biochem. 1994, 222, 515-523.

Mimics of D-myo-Inositol 1,4,5-Trisphosphate
J . Org. Chem., Vol. 61, No. 22, 1996 7723
Meth yl 4,6-O-(p-Meth oxyben zylid en e)-r-D-glu cop yr a n -
osid e (6). A 1 L flask containing methyl-R-D-glucopyranoside
(131 g, 0.68 mol), p-methoxybenzaldehyde dimethyl acetal11
(122 mL, 0.71 mol), p-toluenesulfonic acid (2 g), and DMF (500
mL) was fitted with an air condenser, attached to a water
pump via a three-way tap, and evacuated. The system was
stirred at 70 °C until MeOH ceased to condense (4 h). The
solution was cooled, and the solvents were evaporated in vacuo
to give a white residue. Crystallization from 2% w/v aqueous
NaHCO3 solution (11 L) gave the title compound as fine white
mL), dried (MgSO4), filtered, and concentrated to give crude
9 (11.8 g). Crystallization from EtOH gave pure 9 (10.9 g,
87%): TLC (hexane/EtOAc 4:6) Rf ) 0.60; mp 144-145 °C;
[R]D ) -30.0 (c 1.2, CHCl3); 1H NMR (CDCl3, 270 MHz) δ 3.40
(s, 3 H, OCH3), 3.50-3.59 (m, 2 H, C-2-H, C-4-H), 3.64-3.98
(m, 8 H, C-5-H, C-6-Hax, 2 × ArOCH3), 4.02 (t, J ) 9.1Hz, 1
3
2
H, C-3-H), 4.39 (dd, J 6-Heq,H-5 ) 4.3Hz, J 6-Heq,6-Hax ) 9.8Hz,
1 H, C-6-Heq), 4.57 (d, J ) 3.7Hz, 1 H, C-1-H), 4.67-4.88 (m,
4 H, 2 × ArCH2O AB systems), 5.50 (s, 1 H, C-7-H), 6.82-
6.92 (m, 4 H, 2 × C-3-H and C-5-H of p-substituted rings),
7.25-7.43 (m, 9 H, aromatic CH); 13C NMR (CDCl3, 100.4
MHz) δ 55.2, 55.3, 55.3 (3 × OCH3), 62.3 (CH), 69.0 (C-6), 73.8,
75.0 (2 × ArCH2O), 78.3, 79.2, 82.1 (CH), 99.3 (C-1), 101.2 (C-
7), 113.6, 113.7 (2 × C-3 and C-5 of p-substituted rings), 127.3,
127.9, 128.1, 128.4, 129.7, 130.0 (aromatic CH), 130.9 (C-1 of
p-substituted ring[s]), 138.2 (C-1 of benzyl ring), 159.2, 160.0
(2 × C-4 of p-substituted rings); MS m/ z (+ve ion FAB) 523
[(M + H)+, 10]. Anal. Calcd for C30H34O8: C, 68.94; H, 6.56.
Found: C, 68.9; H, 6.67.
needles (177 g, 84%): mp 202 °C (lit.11 mp 194 °C); [R]D
)
+88.4 (c 1.2, DMF) (lit.11 [R]D +97.4).
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 (7) a n d Meth yl 3-O-Ben zyl-4,6-O-(p-
m eth oxyben zylid en e)-r-D-glu cop yr a n osid e (8). A mix-
ture of 6 (15.5 g, 49.7 mmol), dibutyltin oxide (13.6 g, 54.6
mmol), and tetrabutylammonium iodide (18.4 g, 49.8 mmol)
was heated under reflux for 2 h in MeCN (600 mL) via a
Soxhlet thimble containing 4 Å molecular sieves. The solution
was cooled to room temperature and benzyl bromide (6.5 mL,
54.6 mmol) was added. The system was heated under reflux
for a further 16 h and then cooled. Triethylamine (25 mL)
was added, and stirring was continued for 3 h. The solvents
were evaporated, and the orange residue was extracted with
Et2O (500 mL). The ethereal extract was vigorously stirred
with saturated aqueous NaHCO3 solution (200 mL) for 2 h,
and the resulting suspension was filtered through Celite. The
organic layer was collected, washed with H2O (200 mL), dried
(MgSO4), filtered, and concentrated. The white residue thus
obtained was subjected to flash chromatography (hexane/
EtOAc 7:3) to give 7 (9.6 g, 48%): TLC (hexane/EtOAc 4:6) Rf
) 0.53; mp 135-136.5 °C (from EtOH); [R]D ) +31.9 (c 1.3,
CHCl3); 1H NMR (CDCl3, 400 MHz) δ 2.65 (d, J ) 2.0 Hz, 1 H,
D2O ex , OH), 3.37 (s, 3 H, OCH3), 3.44-3.49 (m, 2 H, C-2-H,
C-4-H), 3.68 (t, J ) 10 Hz, 1 H, 6-Hax), 3.78 (s, 3 H, ArOCH3),
3.77-3.80 (m, 1 H, C-5-H), 4.13 (td, J ) 2.0 Hz, 9.7Hz, 1 H,
Met h yl 2-O-Ben zyl-3,6-b is-O-(p -m et h oxyb en zyl)-r-D-
glu cop yr a n osid e (10) a n d Meth yl 2-O-Ben zyl-3,4-bis-O-
(p-m eth oxyben zyl)-r-D-glu cop yr a n osid e (11). (a) A solu-
tion, kept at 0 °C, of trimethylsilyl chloride (12.5 mL, 98.4
mmol) in dry acetonitrile (15 mL) was added dropwise under
N2 to a vigorously stirred mixture of 9 (8.6 g, 16.4 mmol),
sodium cyanoborohydride (6.2 g, 98.4 mmol), 3 Å molecular
sieves, and dry acetonitrile (150 mL) at 0 °C. The suspension
was allowed to warm to room temperature and was stirred
under N2 for 3.5 h, when TLC (hexane/EtOAc 2:3) indicated
conversion of starting material (Rf ) 0.62) into a minor product
(Rf ) 0.51) and a major product (Rf ) 0.28). The suspension
was filtered through Celite into ice-cold saturated aqueous
NaHCO3 solution (300 mL), and the residue was washed with
acetonitrile. The aqueous layer was extracted with Et2O (2 ×
200 mL), and the combined organic extracts were washed with
saturated aqueous NaHCO3 solution (250 mL), dried (MgSO4),
filtered, and concentrated. The yellow residue thus obtained
was subjected to flash chromatography (eluent hexane/EtOAc
7:3) to give 10 as a colorless oil (2.4 g, 28%): [R]D ) +12.6 (c
2.7, CHCl3); 1H NMR (CDCl3; 270 MHz) δ 2.36 (br s, 1 H,
D2Oex, OH), 3.38 (s, 3 H, OCH3), 3.48-3.79 (m, 6 H, C-2-H,
C-3-H, C-4-H, C-5-H, C-6-H, C-6-H′), 3.78, 3.79 (2 s, 6 H, 2 ×
OCH3), 4.43-4.93 (m, 7 H, C-1-H, 3 × ArCH2O AB systems),
6.83-6.90 (m, 4 H, C-3-H and C-5-H of PMB rings), 7.22-
7.36 (m, 9 H, aromatic CH); 13C NMR (CDCl3; 67.8 MHz) δ
55.1, 55.2 (2 × OCH3), 69.2 (C-6), 69.8, 70.7 (C-4, C-5), 73.1,
73.2, 75.0 (3 × ArCH2O), 79.5, 81.0 (C-2, C-3), 98.1 (C-1), 113.7,
113.9 (2 × C-3 and C-5 of PMB rings), 127.8, 128.0, 128.4,
129.2, 129.6 (aromatic CH), 130.0, 130.9 (2 × C-1 of PMB
rings), 138.0 (C-1 of benzyl ring), 159.1, 159.3 (2 × C-4 of PMB
rings); MS m/z (-ve ion FAB) 523 [(M - H)-, 70], 677 [(M +
NBA)-, 80]. Anal. Calcd for C30H36O8: C, 68.67; H, 6.92.
Found: C, 68.9; H, 6.91.
A sample of 10 was converted into its syrupy 4-O-benzoyl
ester 12 with benzoyl chloride in pyridine: [R]D ) -12.1 (c
2.2, CHCl3); 1H NMR (CDCl3; 270 MHz) δ 3.43 (s, 3 H, OCH3),
3.42-3.54 (m, 2 H, C-6-H, C-6-H′), 3.62-3.67 (m, 4 H, OCH3,
C-2-H), 3.70 (s, 3 H, OCH3), 3.94 (ddd, J )3.5, 9.2, 9.8 Hz, 1
H, C-5-H), 4.03 (t, J ) 9.5 Hz, 1 H, C-3-H), 4.37, 4.41 (AB, J AB
) 13.1 Hz, 2 H, ArCH2O), 4.53-4.85 (m, 5 H, C-1-H, 2 ×
ArCH2O AB systems) 5.28 (t, 1 H, J ) 9.7 Hz, C-4-H), 6.59 (d,
J ) 8.6 Hz, 2 H, C-3-H and C-5-H of PMB ring), 6.71 (d, J )
8.6 Hz, 2 H, C-3-H and C-5-H of PMB ring), 7.04 (d, J ) 8.6
Hz, 2 H, C-2-H and C-6-H of PMB ring), 7.15 (d, J ) 8.6Hz, 2
H, C-2-H and C-6-H of PMB ring), 7.25-7.56 (m, 8 H, aromatic
CH), 7.90-7.94 (m, 2 H, C-2-H and C-6-H of benzoyl ring);
MS m/z (+ve ion FAB) 628 [(M + H)+, 10].
2
D2O shake gives t, C-3-H), 4.23 (dd, J 6-Heq,6-Hax ) 10 Hz,
3J 6-Heq,H-5 ) 4.6 Hz, 1 H, C-6-Heq), 4.60 (d, J ) 3.4 Hz, 1 H,
C-1-H), 4.69, 4.78 (AB, J AB )12.2 Hz, 2 H, C6H5CH2O), 5.47
(s, 1 H, C-7-H), 6.87 (d, J ) 8.8 Hz, 2 H, C-3-H and C-5-H of
p-methoxyphenyl ring), 7.25-7.42 (m, 7 H, aromatic CH); 13
C
NMR (CDCl3, 100.4 MHz) δ 55.3, 55.3 (2 × OCH3), 62.0 (CH),
68.9 (C-6), 70.2 (CH), 73.2 (C6H5CH2O), 73.3, 79.5 (CH), 98.5
(C-1), 101.9 (C-7), 113.6 (C-3 and C-5 of p-methoxyphenyl ring),
127.6, 127.6, 128.0, 128.1, 128.5 (aromatic CH), 129.6 (C-1 of
p-methoxyphenyl ring), 137.9 (C-1 of benzyl ring), 160.1 (C-4
of p-methoxyphenyl ring); MS m/ z (+ve ion FAB) 403 [(M +
H)+, 40]. Anal. Calcd for C22H26O7, 65.64; H, 6.52. Found:
C, 65.4; H, 6.47.
Further elution gave 8 (2.2 g, 11%): TLC (hexane/EtOAc
4:6) Rf ) 0.35; mp 176-178 °C (from EtOH); [R]D ) +76.2 (c
1.7, CHCl3); 1H NMR (CDCl3, 270 MHz) δ 2.42 (d, J ) 7.3 Hz,
1 H, D2O ex, OH), 3.43 (s, 3 H, OCH3), 3.58-3.84 (m, 8 H,
C-2-H, C-3-H, C-4-H, C-5-H, C-6-Hax, ArOCH3), 4.34 (dd,
3J 6-Heq,H-5 ) 3.8 Hz, 2J 6-Heq,6-Hax ) 9.3 Hz, 1 H, C-6-Heq), 4.75-
4.96 (m, AB, J AB ) 11.5 Hz, 3 H, C6H5CH2O overlapping with
C-1-H), 5.51 (s, 1 H, C-7-H), 6.90 (d, J ) 8.8 Hz, 2 H, C-3-H
and C-5-H of p-methoxyphenyl ring), 7.24-7.42 (m, 7 H,
aromatic CH); 13C NMR (CDCl3, 67.8 MHz) δ 55.2 , 55.3 (2 ×
OCH3), 62.5 (CH), 68.9 (C-6), 72.3 (CH), 74.7 (C6H5CH2O), 78.8,
81.8 (CH), 99.8 (C-1), 101.2 (C-7), 113.5 (C-3 and C-5 of
p-methoxyphenyl ring), 127.3, 127.6, 127.9, 128.3 (aromatic
CH), 129.8 (C-1 of p-methoxyphenyl ring), 138.5 (C-1 of benzyl
ring), 160.0 (C-4 of p-methoxyphenyl ring); MS m/ z (+ve ion
FAB) 403 [(M + H)+, 30]. Anal. Calcd for C22H26O7: C, 65.64;
H, 6.52. Found: C, 65.5; H, 6.48.
Met h yl 2-O-Ben zyl-3-O-(p -m et h oxyb en zyl)-4,6-O-(p -
m eth oxyben zylid en e)-r-D-glu cop yr a n osid e (9). A solu-
tion of 7 (9.6 g, 23.8 mmol) in dry DMF (50 mL) was
sequentially treated with NaH (857mg of an 80% w/w disper-
sion in mineral oil, 28.6 mmol) and p-methoxybenzyl chloride
(3.4 mL, 25.0 mmol). The mixture was stirred at room
temperature for 3 h. Methanol (10 mL) was added, and
stirring was continued for 1 h. The solvents were evaporated,
and the residue was extracted with CHCl3 (3 × 150 mL). The
combined organic extracts were washed with H2O (2 × 100
Further elution (eluent hexane/EtOAc 2:3) gave 11 as a pale
yellow oil that solidified to a waxy solid (mp 50-51.5 °C) on
standing (4.1 g, 48%): [R]D ) +7.5 (c 1.1, CHCl3); 1H NMR
(CDCl3; 400 MHz) δ 1.85 (br s, 1 H, D2Oex, OH), 3.35 (s, 3 H,
OCH3), 3.45-3.50 (m, 2 H, C-2-H, C-4-H), 3.59-3.76 (m, 3 H,
C-5-H, C-6-H, C-6-H′), 3.78, 3.79 (2 s, 6 H, 2 × ArOCH3), 3.97
(t, 1 H, J ) 9.3 Hz, C-3-H), 4.55-4.99 (m, 7 H, C-1-H, 3 ×
ArCH2O AB systems), 6.84-6.88 (m, 4 H, 2 × C-3-H and
C-5-H of PMB rings), 7.20-7.38 (m, 9 H, aromatic CH); 13C

7724 J . Org. Chem., Vol. 61, No. 22, 1996
J enkins et al.
NMR (CDCl3; 67.8 MHz) δ 55.1, 55.2 (2 × OCH3), 61.8 (C-6),
70.6 (C-5), 73.4, 74.6, 75.4 (3 × ArCH2O), 77.5, 80.0, 81.7 (C-
2, C-3, C-4), 98.1 (C-1), 113.8, 113.8 (2 × C-3 and C-5 of PMB
rings), 127.8, 128.0, 128.4, 129.6, 129.6 (aromatic CH), 130.3,
130.9 (2 × C-1 of PMB rings), 138.1 (C-1 of benzyl ring), 159.1,
159.3 (2 × C-4 of PMB rings); MS m/z (-ve ion FAB) 677 [(M
+ NBA)-, 60]. Anal. Calcd for C30H36O8: C, 68.67; H, 6.92.
Found: C, 68.6; H, 7.05.
A sample of 11 was converted to its 6-O-benzoyl ester 13
with benzoyl chloride in pyridine: TLC (hexane/EtOAc 2:3)
Rf ) 0.64; mp 120.5 °C (from 2-propanol); [R]D ) +86.2 (c 1.2,
CHCl3); 1H NMR (CDCl3; 270 MHz) δ 3.38 (s, 3 H, OCH3),
3.54-3.62 (m, 2 H, C-2-H, C-4-H), 3.72, 3.81 (2 s, 6 H, 2 ×
ArOCH3), 3.92 (dq, J ) 2, 9.6 Hz, 1 H, C-5-H), 4.03 (t, J ) 9.2
Hz, 1 H, C-3-H), 4.46-4.97 (m, 9 H, 3 × ArCH2O AB systems,
C-1-H, C-6-H, C-6-H′), 6.80 (d, J ) 8.6 Hz, 2 H, C-3-H and
C-5-H of PMB ring), 6.89 (d, J ) 8.6 Hz, 2 H, C-3-H and C-5-H
of PMB ring), 7.17-8.14 (m, 14 H, aromatic CH); MS m/z (+ve
ion FAB) 628 [M+, 5]. Anal. Calcd for C37H40O9: C, 70.68; H,
6.41. Found: C, 70.9; H, 6.30.
to warm to room temperature with stirring for an additional
1 h, and then the solvent was evaporated to give a brown oil.
Purification by flash chromatography (EtOAc/pentane 1:3)
gave 15 as a waxy solid (2.23 g, 86%): [R]D ) -23 (c 1, CHCl3);
1H NMR (CDCl3, 270 MHz) δ 3.21 (dd, J ) 9.3, 9.2 Hz, 1 H,
C-4-H), 3.37 (s, 3 H, OCH3), 3.50 (dd J ) 9.7, 3.2 Hz, 1 H,
C-2-H), 3.79, 3.80 (2 s, 6H, 2 × ArOCH3), 3.96 (dd, J ) 9.5,
9.2 Hz, 1 H, C-3-H), 4.02 (dd, J ) 9.3, 6.8 Hz, 1 H, C-5-H),
4.51-4.90 (m, 6 H, 3 × ArCH2O AB systems), 4.58 (d, J ) 3.2
Hz, 1 H, C-1-H), 5.26 (br d, J ) 10.1 Hz, 1 H, C-7-H, cis), 5.40
(br d, J ) 17.2 Hz, 1 H, C-7-H, trans), 5.88 (ddd, J ) 17.2,
10.1 Hz, 6.8 Hz, 1H, C-6-H), 6.83-7.36 (m, 13 H, aromatic CH);
13C NMR (CDCl3, 67.8 MHz) δ 55.1, 55.3 (OCH3), 71.4 (CH),
73.4, 74.8, 75.5 (ArCH2O), 79.8, 81.4, 82.0 (CH), 98.1 (C-1),
113.8, 113.8 (2 × C-3 and C-5 of PMB rings), 118.0 (C-7), 127.8,
128.1, 128.4, 129.6, 129.6 (aromatic CH), 130.4, 131.1 (2 × C-1
of PMB rings), 135.3 (C-6), 138.2 (C-1 of benzyl ring), 159.2,
159.3 (2 × C-4 of PMB rings); MS m/ z (+ve ion FAB) 519 [(M
- H)+ , 2.0)], 121 [(CH2C6H4OCH3)+, 100], 91 [(C7H7)+ 20]; MS
m/ z (-ve ion FAB) 673 [(M + NBA)-, 25], 399 [(M -
CH2C6H4OCH3)-, 100]. Anal. Calcd for C31H36O7: C, 71.52;
H, 6.97. Found: C, 71.5; H, 7.07.
(b) To a solution of 9 (5.7 g, 10.9 mmol) in freshly distilled,
dry THF (200 mL) was added LiAlH4 (2 g) in one portion. The
mixture was gradually brought to refluxing temperature.
After 1 h, AlCl3 (6 g) was carefully added in portions over 30
min. The mixture was stirred under reflux for a further 2 h
and then cooled to 0 °C. Excess LiAlH4 was destroyed by
careful addition of EtOAc (20 mL), and Al(OH)3 was precipi-
tated by addition of water (30 mL). The system was extracted
with Et2O (300 mL), and the combined organic extracts were
washed with H2O (200 mL), dried (MgSO4), filtered, and
concentrated. Flash chromatography (eluent hexane/EtOAc
7:3) of the concentrate gave exclusively 11 (4.2 g, 73%).
Met h yl 2-O-Ben zyl-3,4-b is-O-(p -m et h oxyb en zyl)-r-D-
glu co-h exod ia ld op yr a n osid e (1,5) (14). Dry DMSO (0.33
mL) was added dropwise to a 2 M solution of oxalyl chloride
in CH2Cl2 (1.25 mL, 2.5 mmol) at -60 °C under N2. After 5
min, a solution of 11 (1.2 g, 2.3 mmol) in CH2Cl2 (5 mL) was
added dropwise over 5 min. The mixture was stirred at -60
°C for 20 min when Et3N (1.2 mL, 9.2 mmol) was added. After
a further 10 min, the mixture was allowed to warm to room
temperature. The solvents were evaporated, and the residue
was subjected to flash chromatography (eluent EtOAc/hexane
3:2) to give the crude product, which showed OH stretching
at νmax 3480 cm-1 in the IR spectrum. The product was
dissolved in toluene (150 mL) and heated under reflux for 3 h
with continuous azeotropic removal of water (Dean-Stark
trap). The solution was cooled and concentrated to give the
pure title compound as a pale yellow oil (1.0 g, 84%): TLC
(EtOAc) Rf ) 0.62 with streaking; [R]D ) +19.6 (c 4.0, CHCl3);
1H NMR (CDCl3; 400 MHz) δ 3.36 (s, 3 H, OCH3), 3.47 (dd, J
) 3.4, 9.3 Hz, 1 H, C-2-H), 3.53 (t, J ) 8.8, 10.3 Hz, 1 H, C-4-
H), 3.79, 3.80 (2 s, 6 H, 2 × ArOCH3), 4.05 (t, J ) 9.3 Hz, 1 H,
C-3-H), 4.13 (d, J ) 10.3 Hz, 1 H, C-5-H), 4.53-4.93 (m, 7 H,
3 × ArCH2O AB systems, C-1-H), 6.85-6.89 (m, 4 H, C-3-H
and C-5-H of PMB rings), 7.15-7.36 (m, 9 H, aromatic CH),
9.62 (s, 1 H, C-6-H); 13C NMR (CDCl3; 100.4 MHz) δ 55.3, 55.7
(2 × OCH3), 73.6 (ArCH2O), 74.3 (C-5), 74.7, 75.6 (2 ×
ArCH2O), 77.5, 79.3, 81.5 (C-2, C-3, C-4), 98.4 (C-1), 113.9 (C-3
and C-5 of PMB rings), 128.1, 128.2, 128.5, 128.6, 129.0, 129.6,
129.7, 129.8 (aromatic CH), 129.9, 130.6 (2 × C-1 of PMB
rings), 137.9 (C-1 of benzyl ring), 159.3, 159.5 (2 × C-4 of PMB
rings), 197.6 (C-6); MS m/z (-ve ion FAB) 677 [(M + NBA)-,
(1R,2S,3S,4R,5S)-3-(Ben zyloxy)-4-h yd r oxy-1,2-b is[(p -
m et h oxyb en zyl)oxy]-5-vin ylcyclop en t a n e (16) a n d
(1R,2S,3S,4S,5R)-3-(Ben zyloxy)-4-h ydr oxy-1,2-bis[(p-m eth -
oxyb en zyl)oxy]-5-vin ylcyclop en t a n e (17). Zirconocene
dichloride (672 mg, 2.30 mmol) was placed into a dry 100 mL
flask under N2, followed by THF (10 mL). The suspension was
cooled to -78 °C, and n-BuLi (1.84 mL of a 2.5 M solution in
hexane, 4.60 mmol) was added. The mixture was stirred at
-78 °C for 1 h, and then a solution of the vinyl carbohydrate
15 (1.00 g, 1.92 mmol) in THF (8 mL) was added. The clear
yellow solution was allowed to reach room temperature, and
stirring was continued for 3 h, during which time it gradually
darkened to reddish orange. The solution was cooled to 0 °C,
and a solution of boron trifluoride etherate (0.45 mL, 3.7 mmol)
in THF (5 mL) was added. Stirring was continued at room
temperature, and TLC (CH2Cl2/EtOAc 10:1) showed conversion
of starting material (Rf ) 0.72) to a major product (Rf ) 0.56)
within 30 min. After 45 min, TLC showed that PMB groups
were being lost. HCl (1 M, 50 mL) was added and the mixture
extracted with CH2Cl2 (2 × 50 mL). The organic extracts were
combined, washed with brine (100 mL), dried (MgSO4), and
concentrated to give a yellow oil, which was purified by column
chromatography (CH2Cl2/Me2CO 30:1) to give the major dia-
stereoisomer 16 (433 mg, 46%) as a waxy solid. A small
amount of the minor diastereoisomer 17 was also isolated (∼30
mg, 3%).
Ma jor Dia ster eoisom er (16): TLC (CH2Cl2/acetone 30:1)
Rf ) 0.32; [R]D ) +9 (c 1, CHCl3); 1H NMR (CDCl3, 400 MHz)
δ 1.99 (d, J ) 4.22 Hz, D2
O ex, 1 H, C-4-OH), 2.86 (ddd, J )
7.8, 7.8, 6.2 Hz, 1 H, C-5-H), 3.77, 3.78 (2s, 6H, 2 × OCH3),
3.77 (obscured by OCH3
, 1 H, C-3-H), 3.93-4.01 (m, 2 H, C-1-H
and C-2-H), 4.11 (m, D2O ex gives dd, J ) 6.0, 3.1 Hz, 1 H,
C-4-H), 4.45-4.65 (m, 6 H, 3 × ArCHO AB systems), 5.23 (br
d, J ) 17.2 Hz, 1 H, dCH2
, trans), 5.25 (br d, J ) 10.6 Hz, 1
H, dCH2, cis), 5.91 (ddd, J ) 17.2, 10.8, 8.0 Hz, 1 H, CH)),
6.83-6.87 (m, 4 H, C-3-H and C-5-H of PMB rings), 7.20-
7.25 (m, 4 H, C-2-H and C-6-H of PMB rings), 7.28-7.35 (m,
5 H, C6
H5); 13C NMR (CDCl3, 67.8 MHz) δ 51.0 (C-5), 55.2 (2
× OCH3), 71.6 (OCH2Ar), 71.6 (2 × OCH2Ar), 75.4, 84.5, 87.2,
87.9 (C-1, C-2, C-3, C-4), 113.7, 113.7 (C-3 and C-5 of PMB
rings), 118.8 (dCH2), 127.7, 127.7, 128.4, 129.4, 129.5 (aro-
matic CH), 130.1, 130.4 (2 × C-1 of PMB rings), 134.7 (CHd),
138.1 (C-1 of benzyl ring), 159 2, 159.1 (C-4 of PMB rings);
MS m/ z (+ve ion FAB) 489 [ (M - H)+, 1.2)], 369 [(M -
60]; IR (liquid film) νmax 1745 cm-1
.
Anal. Calcd for
C30H34O8: C, 68.94; H, 6.56. Found: C, 68.7; H, 6.63.
Meth yl 2-O-Ben zyl-6,7-d id eoxy-3,4-bis-O-(p-m eth oxy-
ben zyl)-r-D-glu co-h ep t-6-en op yr a n osid e (1,5) (15). A dry
100 mL flask was charged with methyltriphenylphosphonium
bromide (3.70 g, 10.4 mmol), previously dried in vacuo at 60
°C. Dry THF (10 mL) was added and the suspension was
cooled to -10 °C, with stirring, under N2. Potassium tert-
butoxide (9.8 mL of a 1.0 M solution in dry THF) was added,
and the yellow suspension was allowed to reach room tem-
CH2C6H4OCH3)+ 6.0), 121 [(CH2C6H4OCH3)+, 100]; MS m/ z
,
(-ve ion FAB) 643 [ (M + NBA)- , 100]. Anal. Calcd for
C30H34O6: C, 73.45; H, 6.99. Found: C, 73.2; H, 7.05.
Min or Dia ster eoisom er (17): TLC (CH2Cl2/acetone 30:
1) Rf ) 0.36; mp 83-85 °C (from EtOH); [R]D ) -26 (c 1,
CHCl3); 1H NMR (CDCl3, 400 MHz) δ 2.53 (d, J ) 8.3 Hz, 1 H,
D2O ex, C-4-OH), 2.71 (ddd, J ) 8.3, 7.8, 7.8 Hz, 1 H, C-5-H),
3.66 (dd J ) 7.8, 4.4 Hz, 1 H, C-1-H), 3.79, 3.80 (2s, 6 H, 2 ×
OCH3), 3.79-3.87 (m, partly obscured by OCH3, 2 H, C-3-H
and C-4-H), 3.94 (dd, J ) 4.3, 2.44 Hz, 1 H, C-2-H), 4.43-4.69
perature. After being stirred for
a further 10 min, the
suspension was cooled to -10 °C and a solution of 14 (2.60 g,
4.98 mmol) in dry THF (5 mL) was added. The color darkened
to deep orange almost immediately, the mixture was allowed

Mimics of D-myo-Inositol 1,4,5-Trisphosphate
J . Org. Chem., Vol. 61, No. 22, 1996 7725
(m, 6 H, 3 × ArCH2O AB systems), 5.16 (br d, J ) 10.3 Hz, 1
H, dCH2, cis), 5.23 (br d, J ) 17.1 Hz, dCH2, 1 H, trans), 5.84
(ddd, J ) 17.1, 10.3 7.8 Hz, 1 H, CHd), 6.85-6.89 (m, 4 H,
C-3-H and C-5-H of PMB rings), 7.31-7.37 (m, 4 H, C-2-H and
C-6-H of PMB rings), 7.31-7.37 (m, 5 H, aromatic CH); 13C
NMR (CDCl3, 67.8 MHz) δ 53.7 (C-5), 55.2 (2 × OCH3), 71.5,
71.6, 71.8 (OCH2Ar), 73.8, 81.8, 85.2, 86.1 (C-1, C-2, C-3, C-4),
113.7, 113.8 (C-3 and C-5 of PMB rings), 117.1 (dCH2), 127.8,
127.9, 128.4, 129.4, 129.4 (aromatic CH), 129.9, 130.2 (2 × C-1
of PMB rings), 137.6 (C-1 of benzyl ring), 137.8 (CHd), 159.1,
159.3 (C-4 of PMB rings); MS m/ z (+ve ion FAB) 489 [(M -
H)+ , 1.0)], 369 [(M - CH2C6H4OCH3)+, 5.0), 121 [(CH2C6H4-
OCH3)+, 100]; 91 [(C7H7)+, 10]. Anal. Calcd for C30H34O6: C,
73.45; H, 6.99. Found: C, 73.6; H, 7.02.
(1R ,2S ,3S ,4R ,5R )-3-(Be n zyloxy)-1,2,4-t r ih yd r oxy-5-
vin ylcyclop en ta n e (18). To a solution of 16 (175 mg, 0.357
mmol) in EtOH (40 mL) was added 1 M HCl (20 mL). The
solution was refluxed for 3 h, and then the solvents were
removed by evaporation in vacuo. The residue was taken up
in EtOAc (50 mL) and washed with saturated NaHCO3
solution and brine (25 mL of each). The combined aqueous
layers were reextracted with EtOAc (50 mL), and the combined
organic layers were then dried (MgSO4) and concentrated to
give a yellow oil. Purification by column chromatography
(CHCl3/MeOH 5:1) gave the triol 18 as a waxy solid: mp 64-
66 °C (78 mg, 87%); [R]D ) +53 (c 1, CHCl3); 1H NMR (CDCl3,
400 MHz) δ 2.55 (ddd, J ) 9.3, 7.8, 7.3 Hz, 1 H, C-5-H), 2.79
(br s, 1 H, D2O ex, OH), 2.92 (br s, D2O ex, 1 H, OH), 3.65 (dd
J ) 5.4, 2.0 Hz, 1 H, C-3-H), 3.88 (br dd, 1 H, D2O ex gives dd,
J ) 7.3, 5.4 Hz, C-2-H), 3.95-4.00 (br m, 2 H, sharpens on
D2O ex, C-1-H and C-4-H), 4.10 (br s, 1 H, D2O ex, OH), 4.54,
4.58 (AB, J AB ) 11.7 Hz, 2 H, OCH2C6H5), 5.20 (dd, J ) 17.1,
1.6 Hz, 1H, dCH2, trans), 5.23 (dd, J ) 10.3, 1.6 Hz, 1 H,
dCH2, cis), 5.82 (ddd, J ) 17.1, 10.3, 7.8 Hz, 1 H, CHd), 7.22-
7.32 (m, 5 H, C6H5); 13C NMR (CDCl3, 100.4 MHz) δ 51.5 (C-
5), 71.8 (OCH2C6H5), 74.7, 76.7, 81.5, 89.1 (C-1, C-2, C-3, C-4),
119.6 (dCH2), 127.9, 127.9, 128.5 (aromatic CH), 133.77
(CH)), 137.8 (C-1 of benzyl ring); MS m/ z (+ve ion FAB) 501
[(2M + H)+, 2.0], 249 [(M - H)+, 5.0)], 149 (30), 91 [(C7H7)+,
100]; MS m/ z (-ve ion FAB) 403 [(M + NBA)- , 100], 249 [(M
- H)-, 50)], 149 (50). Anal. Calcd for C14H18O4: C, 67.18; H,
7.25. Found: C, 66.9; H, 7.44.
(1R,2R,3S,4R,5S)-3-(Ben zyloxy)-1,2,4-tr is[[bis(ben zyl-
oxy)p h osp h or yl]oxy]-5-vin ylcyclop en ta n e (19). To a so-
lution of bis(benzyloxy)(N,N-diisopropylamino)phosphine (670
mg, 1.94 mmol) in CH2Cl2 (2 mL) was added 1H-tetrazole (200
mg, 2.85 mmol). The mixture was stirred at room temperature
for 10 min, and then the triol 18 (80 mg, 0.320 mmol) was
added. The mixture was stirred for a further 1 h, after which
a 90 MHz 31P NMR spectrum showed signals around 139 ppm
(a singlet and an AB quartet with J ) 6.7 Hz) corresponding
to the trisphosphite triester. The mixture was cooled to -78
°C, and m-CPBA (517 mg, 3.00 mmol) was added. The mixture
was warmed to room temperature, with stirring, and then
diluted with EtOAc (50 mL). The solution was washed with
10% w/v Na2SO3 solution, 1 M HCl, saturated NaHCO3, and
brine (50 mL of each), dried (MgSO4), and concentrated to give
an oil. Purification by column chromatography (CHCl3/acetone
10:1) gave the trisphosphate triester 19 as a colorless oil (271
mg, 82%): [R]D ) +3.5 (c 1, CHCl3); 1H NMR (CDCl3, 400 MHz)
δ 3.02 (m, 1 H), 4.20 (br s, 1 H), 4.50 (AB, J AB ) 11.2Hz, 1 H),
4.68 (br dd, J ) 7.8, 4.9 Hz, 1 H), 4.87-5.08 (m, 14 H), 5.18
(d, J ) 10.3, 1.5 Hz, 1 H), 5.26 (d, J ) 17.1, 1.5 Hz, 1 H), 5.86
(ddd, J ) 17.1, 10.3, 8.3 Hz, 1 H), 7.17-7.33 (m, 35 H); 13C
NMR (CDCl3, 100.4 MHz) δ 50.9 (C-5), 69.2, 69.4, 69.5, 69.6,
72.0 (7 × OCH2C6H5), 81.2, 84.1, 85.6, 86.2 (C-1, C-2, C-3, C-4),
120.7 (dCH2), 127.4, 127.5, 127.7, 127.9, 128.0, 128.1, 128.2,
128.3, 128.5 128.9 (aromatic CH), 131.4 (CHd), 135.4, 135.5,
135.5, 135.6, 135.7, 135.8, 137.3 (7 × C-1 of benzyl ring); 31P
NMR (CDCl3, 161.7 MHz) δ -1.97, -2.12, -2.34; MS m/ z (+ve
ion FAB) 1031 [(M + H)+, 2.5)], 149 (20), 91 [(C7H7)+, 100];
MS m/ z (-ve ion FAB) 938 (14), 277 [(C6H5O)2PO2-, 100].
Anal. Calcd for C56H57O13P3: C, 65.24; H, 5.57. Found: C,
65.0; H, 5.60.
densed into a three-neck flask at -78 °C. An excess of sodium
was added to dry the liquid NH3, and the deep blue solution
was stirred at -78 °C for 30 min. A small volume of the dry
NH3 (∼30 mL) was then distilled into a second three-neck flask
and kept at -78 °C. Sodium was added until the solution
remained blue-black for 10 min. A solution of 19 (80 mg, 78
µmol) in dry dioxane (2 mL) was added to the vigorously-
stirring Na/NH3 mixture. After 60-90 s the reaction was
carefully quenched with MeOH, followed by deionized water.
Ammonia and solvents were then removed by evaporation in
vacuo. The residue was dissolved in deionized water (500 mL)
and purified by ion-exchange chromatography on Q Sepharose
fast flow resin, eluting with a gradient of triethylammonium
bicarbonate buffer (0-1 M), pH 8.0. The glassy triethylam-
monium salt of 3 eluted between 300 and 400 mM. Fractions
containing 3, as judged by Briggs phosphate assay,19 were
combined and concentrated to give a residue from which
MeOH was evaporated three times to give glassy 3 as its
triethylammonium salt (yield 45 µmol, 58%): [R]D ) -8, [R]436
) -28 (c 0.36, TEAB buffer pH 7.8, calcd for free acid); high
-
resolution -ve FAB: m/ z 398.963 (M-) calcd for C7H14O13P3
,
1
398.965; H NMR (D2O, 400 MHz, pH 3.2) δ 2.76 (ddd, J )
8.9, 7.9, 7.9 Hz, 1 H, C-5-H), 3.98 (t, J ) 3.7, 3.7 Hz, 1 H,
C-3-H), 4.14-4.21 (m, 2 H, C-2-H, C-4-H), 4.37 (ddd, J ) 8.9,
8.9, 5.2 Hz, 1 H, C-1-H), 5.07 (br d, J ) 10.4 Hz, 1 H, dCH2,
cis), 5.12 (br d, J ) 17.4 Hz, 1 H, dCH2, trans), 5.75 (ddd, J )
17.4, 10.4, 7.9 Hz, 1 H, CHd); 31P NMR (D2O, 161.7 MHz, pH
1
3.2, H-coupled) δ 1.62 (d, J HP ) 9.0 Hz, 1 P), 1.86 (d, J HP
)
8.8 Hz, 1 P), 2.20 (d, J HP ) 9.0 Hz, 1 P); MS m/ z (+ve ion
FAB) 102 [(C2H5)3NH+, 100]; MS m/ z (-ve ion FAB) 798 [2M-,
10], 399 [M-, 100].
(1R ,2S ,3S ,4R ,5S )-3-(B e n zy lo x y )-4-h y d r o x y -5-(h y -
d r oxym et h yl)-1,2-b is[(p -m et h oxyb en zyl)oxy]cyclop en -
ta n e (20). To a 0.1 M solution of SmI2 in THF (100 mL, 10
mmol) under N2 were added HMPA (5 mL) and freshly
distilled, dry t-BuOH (0.4 mL, 4.3 mmol). A solution of 14
(926 mg, 1.8 mmol) in freshly distilled, dry THF (20 mL) was
then added dropwise over 15 min, and the blue-black mixture
was stirred under a stream of N2 for an additional 1 h. HCl
(1 M, 100 mL) was added, and the mixture was extracted with
Et2O (3 × 150 mL). The combined organic extracts were
washed with 5% w/v aqueous Na2S2O3 solution (100 mL) and
H2O (100 mL), dried (MgSO4), filtered, and concentrated. The
residual orange oil was subjected to flash chromatography
(eluent hexane/EtOAc 3:2) to give 11 (175 mg, 19%).
Further elution with EtOAc gave 20 as a pale yellow oil (321
mg, 37%): TLC (EtOAc) Rf ) 0.49; [R]D ) +19.5 (c 4.1, CHCl3);
1H NMR (CDCl3; 400 MHz) δ 2.24 (m, 1 H), 2.50-3.40 (br s, 2
H, 2 × OH), 3.72-3.77 (m, 7 H), 3.78-3.83 (m, 2 H), 3.90 (t,
J ) 5.4 Hz, 1 H), 3.97 (t, J ) 5.9 Hz, 1 H), 4.24 (dd, J ) 3.9,
6.8 Hz, 1 H), 4.47-4.65 (m, 6 H), 6.83-6.86 (m, 4 H), 7.20-
7.33 (m, 9 H); 13C NMR (CDCl3; 100 MHz) δ 46.7 (C-5), 55.2
(OCH3), 60.9 (CH2OH), 71.7, 71.8 (3 × ArCH2O), 75.2, 81.7,
87.4, 87.9 (C-1, C-2, C-3, C-4), 113.7 (C-3 and C-5 of PMB
rings), 127.7, 127.8, 128.4, 129.4, 129.5 (aromatic CH), 130.1,
130.3 (2 × C-1 of PMB rings), 138.1 (C-1 of benzyl ring), 159.1,
159.2 (2 × C-4 of PMB rings); MS m/z (-ve ion FAB) 493 [(M
- H)-, 50]. Anal. Calcd for C29H34O7: C, 70.41; H, 6.93.
Found: C, 70.5; H, 6.57.
(1R,2S,3S,4R,5S)-3-(Ben zyloxy)-5-[(ben zyloxy)m eth yl]-
4-h yd r oxy-1,2-b is[(p -m et h oxyb en zyl)oxy]cyclop en t a n e
(22) a n d (1R,2S,3S,4R,5S)-3,4-Bis(ben zyloxy)-5-(h yd r oxy-
m eth yl)-1,2-bis[(p-m eth oxyben zyl)oxy]cyclopen tan e (21).
A solution of 20 (200 mg, 0.4 mmol) in dry DMF (3 mL) at 0
°C was sequentially treated with NaH (17mg of a 60% w/w
dispersion in mineral oil, 0.4 mmol) and benzyl bromide (0.05
mL, 0.45 mmol). The mixture was stirred at 0 °C for 1 h, when
TLC (EtOAc/hexane 3:2) indicated two products (Rf ) 0.58 and
0.49) and unreacted starting material (Rf ) 0.15). Methanol
(1 mL) was added, and the solution was stirred for an
additional 5 min. The solvents were evaporated, and the
residue was extracted with CHCl3 (100 mL). The organic
solution was washed with H2O (100 mL) and brine (100 mL),
dried (MgSO4), filtered, and concentrated. The syrupy residue
was subjected to flash chromatography (eluent CHCl3/acetone
30:1) to give 22 as a pale yellow oil (67 mg, 28%): [R]D ) +30.4
(1R,2R,3S,4R,5S)-3-Hyd r oxy-1,2,4-tr is(p h osp h on ooxy)-
5-vin ylcyclop en ta n e (3). Ammonia (∼100 mL) was con-

7726 J . Org. Chem., Vol. 61, No. 22, 1996
J enkins et al.
(c 2.0, CHCl3); 1H NMR (CDCl3; 400 MHz) δ 2.31 (m, J ) 4.9,
9.3 Hz, 1 H, C-5-H), 3.32 (d, J ) 3.4 Hz, 1 H, OH), 3.72-3.78
(m, 2 H, CH2OCH2Ph), 3.77-3.81 (m, 7 H, 2 × OCH3, C-3-H),
3.90 (t, J ) 5.9 Hz, 1 H, C-2-H), 4.06 (dd, J ) 5.9, 9.3 Hz, 1 H,
C-1-H), 4.25 (br m, 1 H, C-4-H), 4.40-4.70 (m, 8 H, 4 ×
ArCH2O AB systems), 6.81-6.87 (m, 4 H, C-2-H and C-5-H of
PMB rings), 7.15-7.37 (m, 14 H, aromatic CH); 13C NMR
(CDCl3; 100.4 MHz) δ 45.4 (C-5), 55.3 (OCH3), 68.0 (CH2OCH2-
Ph), 71.7, 71.8, 72.0, 73.5 (4 × ArCH2O), 75.1, 81.3, 88.0 (4 ×
CH), 113.7 (C-2 and C-5 of PMB rings), 127.6, 127.8, 127.8,
127.9, 128.4, 128.4, 128.5, 129.5, 129.6 (aromatic CH), 130.4,
130.6 (2 × C-1 of PMB rings), 137.5, 138.2 (2 × C-1 of benzyl
rings), 159.2, 159.2 (2 × C-4 of PMB rings); MS m/z (+ve ion
FAB) 463 [(M - PMB)+, 65]. Anal. Calcd for C36H40O7: C,
73.94; H, 6.90. Found: C, 73.8; H, 7.00.
Further elution gave 21 as a pale yellow oil (98 mg, 41%):
[R]D ) +27.9 (c 1.5, CHCl3); 1H NMR (CDCl3; 400 MHz) δ 2.33
(m, J ) 5.9 Hz, 1 H, C-5), 2.57 (br m, 1 H, ex D2O, OH), 3.77,
3.78 (2 s, 6 H, 2 × OCH3), 3.82-3.87 (m, 2 H, CH2OH), 3.88-
3.91 (br m, 1 H, C-3-H), 3.95 (t, J ) 5.9 Hz, 1 H, C-2-H), 4.00-
4.03 (br m, 1 H, C-1-H), 4.12 (dd, J ) 5.9, 8.8 Hz, 1 H, 4-H),
4.46-4.66 (m, 8 H, 4 × ArCH2O AB systems), 6.84-6.87 (m,
4 H, C-3-H and C-5-H of PMB rings), 7.23-7.35 (m, 14 H,
aromatic CH); 13C NMR (CDCl3; 100.4 MHz) δ 46.8 (C-5), 55.3
(OCH3), 61.0 (CH2OH), 71.8, 71.9, 72.2 (4 × ArCH2O), 82.2,
82.4, 85.8, 88.4 (C-1, C-2, C-3, C-4), 113.8 (C-3 and C-5 of PMB
rings), 127.6, 127.7, 128.0, 128.4, 128.5, 128.6, 129.4, 129.5,
129.6 (aromatic CH), 130.3, 130.5 (2 × C-1 of PMB rings),
137.6, 138.0 (2 × C-1 of benzyl rings), 159.2, 159.2 (2 × C-4 of
PMB rings); MS m/z (+ve ion FAB) 463 [(M - PMB)+, 15].
Anal. Calcd for C36H40O7: C, 73.94; H, 6.90. Found: C, 73.7;
H, 6.92.
11.6 Hz, 2 H, PhCH2O), 7.23-7.35 (m, 10 H); 13C NMR (CDCl3;
100.4 MHz) δ 45.9 (C-5), 68.1 (CH2OCH2Ph), 72.0, 73.5 (2 ×
PhCH2O), 74.5, 76.0, 81.0 (C-1, C-2, C-4), 89.2 (C-3), 127.8,
127.9, 128.0, 128.4, 128.6 (aromatic CH), 137.5, 138.0 (2 × C-1
of benzyl rings); MS m/z (+ve ion FAB) 345 [(M + H)+, 15];
MS m/ z (-ve ion FAB) 343 [(M - 1)-, 38], 497 [(M + NBA)-,
98].
(1R,2R,3S,4R,5S)-3-Hyd r oxy-5-(h yd r oxym eth yl)-1,2,4-
tr is(p h osp h on ooxy)cyclop en ta n e (4). Triol 25 was phos-
phitylated and oxidized as described for 18. After workup and
column chromatography the 31P NMR spectrum of 27 showed
three peaks at δP -2.47, -2.16, and -2.08 ppm, but the 1H
NMR spectrum indicated the presence of minor impurities.
This crude product was deprotected as described for 19 and
purified by ion-exchange chromatography on Q Sepharose fast
flow resin, eluting with a gradient of triethylammonium
bicarbonate buffer (0-1 M), pH 7.3. The triethylammonium
salt of 4 eluted between 610-640 mM buffer: [R]D ) -11.0 (c
0.4 calcd for free acid, TEAB, pH 8.6); high resolution -ve FAB
m/ z 402.962 (M - H)-, calcd for C6H12O14P3- 402.960; 1H NMR
(D2O, pH ca. 4, 400 MHz) δ 2.29 (br quintet, J ) 7.3 Hz, 1 H,
2
3
C-5-H), 3.65 (ABX, J AB ) 12 Hz, J ) 6 Hz, 1 H, CHHOH),
2
3
3.71 (ABX, J AB ) 12 Hz, J ) 7.3 Hz, 1 H, CHHOH), 3.94 (t,
J ) 4.6 Hz, 1 H, C-3-H), 4.16-4.31 (m, 3 H, C-1-H, C-2-H,
C-4-H); 31P NMR (D2O, pH ca. 4, 161.7 MHz) δ 0.36 (d, J HP
)
9.3 Hz, 1 P), 0.49 (d, J HP ) 8.8 Hz, 1 P), 0.66 (d, J HP ) 9.2 Hz,
1 P); MS m/z (-ve ion FAB) 403 [(M - H)-, 100].
(1R,2S,3S,4R,5R)-1,2-Bis(b en zyloxy)-3,4-d ih yd r oxy-5-
(h yd r oxym eth yl)cyclop en ta n e (24). Compound 24 was
prepared from 21 using an analogous procedure to that
described for 18: Rf ) 0.2 (EtOAc); 1H NMR (CDCl3; 270 MHz)
δ 2.08 (br m, 1 H, C-5-H), 2.50 (br s, 1 H, OH), 3.17 (br s, 1 H,
OH), 3.78-3.97 (m, 5 H), 4.16 (t, J ) 9 Hz, 1 H), 4.34 (br s, 1
H, OH), 4.39, 4.53 (AB, J AB ) 11.7 Hz, 2 H, PhCH2O), 4.60,
4.73 (AB, J AB ) 11.7 Hz, 2 H, PhCH2O), 7.22-7.33 (m, 10 H,
aromatic CH); 13C NMR (CDCl3; 67.8 MHz) δ 46.9 (C-5), 60.1
(CH2OH), 71.8, 71.8 (2 × PhCH2O), 75.4, 82.0, 82.0, 87.3 (C-1,
C-2, C-3, C-4), 127.7, 127.8, 127.9, 128.0, 128.4, 128.5 (aromatic
CH), 137.5, 138.1 (2 × C-1 of phenyl rings); MS m/ z (+ve ion
FAB) 345 [(M + H)+, 15%]; MS m/ z (-ve ion FAB) 497 [(M +
NBA)-, 95].
(1R ,2S ,3R ,4R ,5S )-1,2-B is (b e n zy lo x y )-3,4-b is [[b is -
(b e n zyloxy)p h osp h or yl]oxy]-5-[[b is(b e n zyloxy)p h os-
p h or yl]oxy]m eth yl]cyclop en ta n e (26). Compound 24 was
phosphitylated and oxidized as described for 18 to give 26: [R]D
) +7.0 (c 4.9, CHCl3); 1H NMR (CDCl3; 270 MHz) δ 2.65 (q, J
) 4.5 Hz, 1 H), 3.89 (m, 1 H), 4.04 (br s, 1 H), 4.28-4.59 (m,
6 H), 4.83-5.02 (m, 14 H), 7.19-7.37 (m, 20H); 31P NMR
(CDCl3; 161.7 MHz) δ -5.09 (sextet, J HP ) 7.5 Hz, 1 P), -4.38
(sextet, J HP ) 8.1 Hz, 1 P), -3.89 (septet, J HP ) 7.8 Hz, 1 P);
MS m/ z (+ve ion FAB) 1125 [(M + H)+, 80].
Further elution with EtOAc gave starting material 20 (50
mg, 25% recovery).
(1R,2S,3S,4R,5S)-3,4-Bis(b en zyloxy)-1,2-b is[(p -m et h -
oxyben zyl)oxy]-5-vin ylcyclop en ta n e (23). Compound 16
(27.4 mg, 60 µmol) was benzylated with NaH and benzyl
bromide in DMF as described for 20 to give 23: TLC (CHCl3/
acetone 10:1) Rf ) 0.7; [R]D ) +3.4 (c 1.6, CHCl3); 1H NMR
(CDCl3; 400 MHz) δ 2.87 (m, 1 H, C-5-H), 3.78, 3.79 (2 s, 6 H,
OCH3), 3.86-4.01 (m, 4 H, C-1-H, C-2-H, C-3-H, C-4-H), 4.47-
4.59 (m, 8 H, 4 × ArCH2O AB systems), 5.17 (dd, J ) 1.8,
10.4 Hz, 1 H, dCH2, cis), 5.23 (dd, J ) 1.0, 17.2 Hz, 1 H, dCH2,
trans), 6.07 (ddd, J ) 9.1, 10.3, 17.3 Hz, 1 H, CHd), 6.83-
6.87 (m, 4 H, C-3-H and C-5-H of PMB rings), 7.21-7.37 (m,
16 H, aromatic CH); 13C NMR (CDCl3; 67.8 MHz) δ 50.0 (C-
5), 54.6 (2 × OCH3), 70.9, 71.1, 71.3 (4 × ArCH2), 81.9, 84.9,
85.1, 87.4 (C-1, C-2, C-3, C-4), 113.1 (C-3 and C-5 of PMB
rings), 117.0 (dCH2), 127.1, 127.7, 128.8, 128.9 (aromatic CH),
129.9, 130.0 (2 × C-1 of PMB rings), 135.2 (CHd), 137.7 (C-1
of benzyl ring[s]), 158.6 (C-4 of benzyl ring[s]); MS m/ z (+ve
ion FAB) 580 [(M+), 15], 459 [(M - PMB)+, 70].
(1R,2S,3R,4R,5S)-1,2-Dih ydr oxy-3,4-bis(ph osph on ooxy)-
5-[(p h osp h on ooxy)m eth yl]cyclop en ta n e (5). Compound
26 was deprotected as described for 19 and purified by ion-
exchange chromatography on Q Sepharose fast flow resin,
eluting with a gradient of triethylammonium bicarbonate
buffer (0-1 M, pH 7.5). The triethylammonium salt of 5 eluted
between 560-600 mM buffer: [R]D ) +8.3 (c 0.36 calcd for
free acid, TEAB, pH 8.6); high resolution -ve FAB m/ z
Det er m in a t ion of t h e St er eoch em ist r y of 20 a n d
Der iva tives. A solution of 23 (30 mg, 52 µmol) in Et2O (5
mL) was added to a saturated aqueous solution of NaIO4 (5
mL) containing OsO4 (4 mg, 17 µmol), and this mixture was
stirred at room temperature for 24 h. The mixture was diluted
with Et2O (15 mL) and H2O (15 mL), and the organic layer
was dried (MgSO4), filtered, and concentrated. The residue
was redissolved in MeOH (5 mL), and NaBH4 (6mg) was
added. After 30 min the mixture was concentrated, and the
residue was partitioned between Et2O (50 mL) and H2O (20
mL). The organic layer was dried (MgSO4), filtered, and
concentrated, and the residue was purified by flash chroma-
tography (CHCl3/acetone 20:1) to give 21 (9 mg, 30%). The
1H NMR spectra of this sample, a sample prepared by the SmI2
route, and a 1:1 mixture of the two were indistinguishable.
(1R,2S,3S,4R,5R)-3-(Ben zyloxy)-5-[(ben zyloxy)m eth yl]-
1,2,4-tr ih yd r oxycyclop en ta n e (25). Compound 25 was
prepared from 22 using an analogous procedure to that
described for 18: TLC (EtOAc) Rf ) 0.31; [R]D ) +30.0 (c 1.7,
-
402.961 (M - H)-, calcd for C6H12O14P3 402.960; 1H NMR
(D2O, pH ca. 4, 400 MHz) δ 2.34 (br m, 1 H), 3.82-3.86 (m, 1
H), 3.95-4.03 (m, 4 H), 4.17-4.21 (br m, 1 H), 4.29-4.33 (m,
1 H); 31P NMR (D2O, pH ca. 4, 161.7 MHz) δ -0.36 (d, J HP
)
9.3 Hz, 1 P), 0.31 (d, J HP ) 8.8 Hz, 1 P), 0.66 (t, J HP ) 6.1 Hz,
1 P); MS m/ z (-ve ion FAB) 403 [(M - H)-, 100].
Ack n ow led gm en t. We thank Mr. K. C. Smith for
assistance with molecular modeling, Drs. S. G. Ward
and C. T. Murphy for preliminary biological evaluations,
and the Biotechnology and Biological Science Research
Council (Intracellular Signalling Programme) and the
Wellcome Trust (Programme Grant 045491) for support.
B.V.L.P. is a Lister Institute Research Professor.
1
CHCl3); H NMR (CDCl3; 400 MHz) δ 2.16-2.23 (br m, 1 H),
3.14 (br s, 1 H), 3.43 (br s, 1 H), 3.61 (dd, J ) 3.4, 6.1 Hz, 1
H), 3.67-3.74 (m, 3 H, CH2OCH2Ph), 3.82 (br t, J ) 6.5 Hz, 1
H), 3.95 (br dd, J ) 7.6 Hz, 1 H), 4.14-4.18 (br m, 1 H), 4.46,
4.48 (AB, J AB ) 11.9 Hz, 2 H, PhCH2O), 4.60, 4.67 (AB, J AB
)
J O961158Y