Synthesis and biological activities of D-chiro-inositol analogues with insulin-like actions

Article abstract of DOI:10.1016/j.ejmech.2016.06.047

D-chiro-inositol (DCI, 1) evokes therapeutic actions in diabetes and insulin resistance but has sub-optimal pharmacokinetic profiles. To investigate what positions on the DCI cyclohexanol ring may be amenable to modification to improve pharmaceutical form

Full text of DOI:10.1016/j.ejmech.2016.06.047

Accepted Manuscript
Synthesis and biological activities of D-chiro-inositol analogues with insulin-like
actions
P.M. Rendle, F. Kassibawi, K.A. Johnston, J.B. Hart, S.A. Cameron, A. Falshaw, G.F.
Painter, K.M. Loomes
PII:
S0223-5234(16)30537-2
10.1016/j.ejmech.2016.06.047
EJMECH 8708
DOI:
Reference:
To appear in: European Journal of Medicinal Chemistry
Received Date: 25 November 2015
Revised Date: 23 June 2016
Accepted Date: 25 June 2016
Please cite this article as: P.M. Rendle, F. Kassibawi, K.A. Johnston, J.B. Hart, S.A. Cameron,
A. Falshaw, G.F. Painter, K.M. Loomes, Synthesis and biological activities of D-chiro-inositol
analogues with insulin-like actions, European Journal of Medicinal Chemistry (2016), doi: 10.1016/
j.ejmech.2016.06.047.
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ACCEPTED MANUSCRIPT
Graphical abstract

ACCEPTED MANUSCRIPT
Synthesis and biological activities of
D-chiro-inositol analogues with insulin-
like actions.
Rendle, P.M.1, Kassibawi, F.2, Johnston, K.A.1, Hart, J.B.1,Cameron, S.A.1, Falshaw, A.1, Painter, G.F.
1,3, & Loomes, K. M.2,3
1Ferrier Research Institute, Victoria University of Wellington, Lower Hutt, 2New Zealand School of
Biological Sciences, University of Auckland, 3Maurice Wilkins Centre for Molecular Biodiscovery,
University of Auckland, New Zealand.
Running title: DCI analogues and bioactivity.
Corresponding authors:
1. Kerry Loomes: School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland,
New Zealand; Telephone +6493737999; Fax: +6493737045; email: k.loomes@auckland.ac.nz.
2. Gavin Painter: The Ferrier Research Institute, Victoria University of Wellington, PO Box 33-436,
Lower Hutt, New Zealand, 5040; Telephone +6444630058; Fax: +6444639030; e-mail:
gavin.painter@vuw.ac.nz.

ACCEPTED MANUSCRIPT
Abstract
-chiro-inositol (DCI, 1) evokes therapeutic actions in diabetes and insulin resistance but has sub-
D
optimal pharmacokinetic profiles. To investigate what positions on the DCI cyclohexanol ring may be
amenable to modification to improve pharmaceutical formulations, a series of analogues based on DCI
were synthesised. These compounds were then evaluated for their ability to stimulate glucose
transport using 3T3-L1 adipocytes as a model system. Positional analyses indicate that the hydroxyl
group at position 1 is not essential for activity and can be modified without affecting glucose uptake.
Removal of the hydroxyl at position 3 also had minimal effect on activity but this group is sensitive to
modification. By comparison, the oxygen at position 2 is crucial to the potency of DCI, although this
group can withstand modification without fundamentally affecting activity. These data reveal that
positions 1 and 2 on the cyclohexanol ring of DCI offer further scope for modification to develop DCI
analogues with desirable pharmacokinetic profiles for the potential treatment of metabolic disease.
1. Introduction
Inositols are naturally occurring carbacyclic polyols (i.e. 1,2,3,4,5,6-cyclohexanehexols) that have
various biological activities [1].
D-chiro-inositol (DCI, 1, Fig. 1) is of interest due to its chiral
properties and biological activity that includes therapeutic actions in diabetes and insulin resistance
[2]. In humans endogenous levels of DCI are derived from the diet and through conversion from its
stereoisomer, myo-inositol, through a putative epimerase enzyme [2]. Evidence suggests that the
therapeutic effects of DCI are due to insulin-like actions whereby its administration in experimental
animal models of diabetes in vivo reduces hyperglycemia [3]. DCI administration also improves
insulin sensitivity in humans with polycystic ovary syndrome (PCOS) [4, 5]. It has been proposed that
DCI replacement therapy may counteract a deficiency of
contributes to impaired insulin action [2].
D-chiro-inositol body stores which
The insulin-like actions of DCI have been attributed to metabolites of various modified forms that
include both phosphorylation and glycosylation of DCI [6]. Two types of such inositol
phosphoglycans have been identified: type-A and type-P. Type-A inositol phosphoglycans contain the
DCI stereoisomer, myo-inositol, and glucosamine, while the type-P phosphoinositol glycans contain
DCI and galactosamine [7-9]. These DCI-containing inositol phosphoglycans may act as second
messengers that mimic insulin action or amplify the insulin-signalling response [10-12]. Interestingly,
the functionally active inositol phosphoglycan forms are confined to type-P inositol phosphoglycans
containing DCI as the core inositol component [2].
The insulin-like actions of DCI appear to be mediated through multiple tissues and metabolic targets
[2, 13]. In skeletal muscle, soluble inositol glycans that contain DCI may increase glucose disposal

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through stimulation of protein phosphatase 2Cα (PP2Cα) and pyruvate dehydrogenase phosphatase
(PDHP) activities [14, 15]. One of these compounds, β-galactosamine-(1-4)-3-O-methyl-D-chiro-
inositol (INS-2), may bind to distinct sites on these two phosphatase enzymes [15, 16]. There is also
evidence that inositol phosphoglycans containing DCI may interact with caveolae and converge with
insulin signalling at the level of insulin receptor substrate-1 (IRS-1) and phosphatidylinositol-3-kinase
(PI3K) [17-19]. Together with actions of DCI on hepatic glucose output [13] and its apparent
depletion in metabolic disease [20-22] these effects could help explain the anti-diabetic and insulin-
sensitizing effects of DCI [5, 23, 24].
As DCI possesses insulin-like activities there is the potential to develop analogues that could be
progressed as potential therapeutics for metabolic disease. However, due to their highly polar nature,
DCI and inositols in general have sub-optimal pharmacokinetic profiles and are rapidly cleared from
the body [25, 26]. For myo-inositol, this has led to the development of specific pharmaceutical
formulations to improve bioavailability [25]. However, the problem of bioavailability could be
resolved by simple modification of the inositol ring to increase lipophilicity, thereby improving
pharmacokinetic properties and bioavailability. Such endeavours would be greatly assisted through
knowledge of what positions on the cycohexanol ring of DCI were amenable to modification.
However, in the absence of defined and validated cellular molecular targets, the structure-activity
relationships governing the functional importance of these individual hydroxyls are unknown. We
therefore designed and carried out an empirical SAR study to explore functional group modification
of the hydroxyl groups on DCI. Here, we report the synthesis of DCI analogues with subsequent
screening of their effects on glucose transport in 3T3-L1 adipocytes as a model cellular system.
2. Results & Discussion
2.1. Chemistry
DCI is an optically active inositol that contains a C2 symmetry element rendering the O-1/6, 2/5 and
3/4 hydroxyl pairings chemically equivalent. Synthesis of the 6-deoxy-D-chiro-inositol analogues
started from diacetonide 11 [27] as shown in Scheme 1. In general, for the synthesis of the deoxy
compounds we found it more convenient to telescope xanthate formation, reduction and removal of
the isopropylidene groups into a single step. Reaction of 11 with carbon disulfide and methyl iodide
generated S-methyl xanthate 12. Inspection of the proton NMR resonance for H-6 (6.45 ppm)
revealed small coupling constants (i.e. < 3 Hz) confirming the expected 4C1 chair conformation [28].
Xanthate 12 was reduced with lauroyl peroxide [29] to give the intermediate 6-deoxygenated
derivative 13 that was unable to be adequately purified so was used in a crude form for the subsequent
step. Treatment with trifluoroacetic acid removed the isopropylidene protecting groups to afford 6-

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deoxy-3-O-methyl-
D
-chiro-inositol 4 after crystallization. Further treatment with hydroiodic acid
afforded 6-deoxy-D-chiro-inositol 3 in 40% yield over 4 steps. Two dimensional NMR spectroscopy
1
and H NMR coupling constants were consistent with the chemical structure allowing a complete
assignment of the proton and carbon NMR spectra (SI) (supplementary material).
The synthesis of 4-deoxy-D-chiro-inositol (6) proceeded via a similar strategy using 1,2;5,6-
diisopropylidene protected pinitol 14 [27] as a starting material (Scheme 2). Reaction of 14 with
carbon disulfide and methyl iodide followed by reduction of the xanthate with lauroyl peroxide
produced a crude intermediate product that was treated with TFA to afford the 4-deoxy compound
14C. The chemical structure of compound 14C was confirmed from mass spectral, a complete NMR
assignment and elemental analysis (supplementary material).
Synthesis of the O-1/O-6 butyl ether 7 began with the alkylation of diol 15 with a procedure [30, 31]
that utilized iodobutane and sodium hydride in DMF (Scheme 3). The reaction was surprisingly
sluggish affording only a moderate amount of the desired mono-butylated intermediate 16 which
required chromatographic separation from the 1,6-di-O-butylated material. In situ deprotection of 16
with trifluoroacetic acid generated 1-O-butyl-D-chiro-inositol 7 in 89% yield. Due to the C2
symmetry element present in diol 15 mono-alkylation at either hydroxyl (i.e.O-1 or O-6) produces the
same compound. The structural assignment of butyl ether 7 can be confirmed from NMR
spectroscopy (supplementary material). In particular, for carbohydrates alkylation of ring hydroxyl
groups consistently results in a downfield chemical shift of the associated ring carbon by 5 – 10 ppm
[32]. For example, for compound 7 the C-1 resonance is observed at 80.1 ppm whereas C-6 resonates
at 69.3 ppm.
Synthesis of the 2-O-butyl-D-chiro-inositol analogue (8) began with reaction of 3,4-di-O-benzyl-D-
chiro-inositol 17 [30] with dibutyltin oxide followed by alkylation with iodobutane in the presence of
caesium fluoride (Scheme 4). This resulted in formation of the mono-alkylated (equatorial oxygen, O-
2/O-5) of the inositol ring, albeit in low yield (29%). Subsequent hydrogenation afforded the target
compound 8 in 92% yield. As above, the alkylated ring methine (C-2) resonance at 79.0 ppm could be
clearly distinguished from the other unalkylated carbons (supplementary material).
Access into the 3-O-butyl- and 3-O-butanoyl-D-chiro-inositols, 9 and 10, was achieved by the initial
reaction of diisopropylidene diol 19 [30, 33, 34] with iodobutane or butyryl chloride respectively
(Scheme 5). Treatment with trifluoroacetic acid successfully removed the isopropylidene groups to
generate the compounds of interest. Consistently, as above the position of alkylation could be
determined by inspection of the ring carbon chemical shift (81.8 ppm) in combination with 2D
examination (supplementary material).

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For ester 10 because we did not have access to the other isomers for comparative studies and, unlike
alkyl groups esters can migrate in certain conditions, we decided to confirm the chemical by single
crystal X-ray crystallography. The ORTEP diagram of 10 is shown in Fig. 2 and selected
crystallographic parameters are given in Table 1. This crystal structure clearly shows the DCI moiety
in the expected chair conformation and the butyl ester present in the 3-position. The structure has no
disorder or solvent of crystallisation, and features an extensive hydrogen-bonding network.
2.2. Structure-activity relationships based on stimulation of glucose transport in 3T3-L1 adipocytes
2.2.1. Stimulation of glucose uptake by DCI
We utilised rat 3T3-L1 adipocytes [35] as an in vitro model system to investigate the insulin-like
effects of the compounds synthesised through the stimulation of glucose uptake. In this assay 2-
deoxy-D
-[2,6-3H]glucose is transported into the cell but not further metabolised. The rate of
intracellular accumulation of this compound therefore directly reflects the glucose transport capacity
of the cell [36]. Although there are potential limitations in the use of 3T3-L1 adipocytes [37, 38] we
nevertheless observed reproducible differentiation from 3T3-L1 fibroblasts (approximately 90%)
characterised by the accumulation of large intracellular lipid droplets as analysed using light
microscopy [35].
We also internally-validated each experiment with a positive control showing that incubation with
insulin increased intracellular 2-deoxy-
and Table 2). Within this experimental context we found that incubation of 3T3-L1 adipocytes with
DCI (1; 200 µM concentration) significantly increased 2-deoxy-
-[2,6-3H]glucose uptake (Fig. 3B),
D
-[2,6-3H]glucose content compared to basal uptake (Fig. 3A
D
with an activity of 64% ± 9% of the insulin response compared to basal. This result confirms that DCI
possesses insulin-like actions that increase intracellular glucose transport.
Interestingly the enantiomeric form of DCI,
L-chiro-inositol (LCI, 2, Fig. 1), also stimulated 2-deoxy-
D
-[2,6-3H]glucose uptake to 43% ± 1% of the absolute insulin response (Fig. 3C). The only difference
between these enantomeric forms is the inversion of the stereochemistry at the 2 and 6 positions
suggesting that the specific orientation of the hydroxyls at these particular positions does not
fundamentally affect activity. The physiological significance of LCI is unknown although both LCI
and DCI display a widespread distribution in a range of rat tissues including skeletal muscle, heart and
smooth muscle [39]. The
urine [39].
D-isomer also predominates in brain and kidney as well as in rat and human
2.2.2. Effect of deoxy-D-chiro-inositols on glucose uptake

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To probe the functional importance of the hydroxyls around the DCI ring we synthesised and tested
various derivatives where hydroxyl groups were selectively removed from around the DCI ring (Table
2 and Fig. 4). The experimental findings revealed that removal of the hydroxyl group from either
position 6 (1) or 4 (3) of the cyclohexanol ring did not greatly impact on the activity of the compound
as both 6-deoxy-D-chiro-inositol (3) and 4-deoxy-D-chiro-inositol (6) stimulated 2-deoxy-D-[2,6-
3H]glucose uptake (22% ± 7% and 40% ± 12% of the insulin response respectively).
The 3-O-methylated derivative of 6-deoxy-DCI (6-deoxy-3-O-methyl-D-chiro-inositol, 4) showed no
activity compared to unmethylated compound 3 implying that the presence of a small alkyl substituent
at O-3 is detrimental to activity. Interestingly, of the two independent experiments performed with the
2/5-deoxygenated derivative, 2/5-deoxy-D-chiro-inositol (5), one showed significant inhibition of
uptake compared to basal activity (0.50 ± 0.1 fold of the basal response) while the other revealed no
significant change from basal. These data indicate that a hydroxyl group is fundamentally required at
position 2/5 although its stereochemistry can be ambiguous as suggested by the activity of LCI (2).
2.2.3. Effect of alkylated inositols on glucose uptake
A second series of inositol derivatives were synthesised where the oxygen atoms around the DCI ring
were selectively butylated (Fig. 4). This modification increases the lipophilicity of these compounds
that may improve their bioavailability. It is also possible that alkylation could enhance cell membrane
permeability or affect binding with intracellular protein targets.
Stimulation of glucose uptake relative to DCI was retained with 1-O-butyl-D-chiro-inositol (7)
although the level of stimulation was markedly reduced compared to the insulin response (8.0 ± 0.3%)
(Table 2 and Fig. 4). Thus, there appears to be scope for modification at O-1/6 of the inositol ring
with retention of some activity. Bioactivity was also retained when the O-2/5 position was modified
(2-O-butyl-D-chiro-inositol, 8) inducing 22% ± 8% of the insulin response.
By contrast, no significant stimulation was observed with the compound 3-O-butyl-
D-chiro-inositol
(9). By comparison, the 3-O-butanoyl- -chiro-inositol compound (10) retained some bioactivity
D
(19% ± 6% of the insulin response). These results may suggest that ester group is removed by
intracellular esterase activity however further investigation would be needed to confirm this finding.
These findings suggest that while the hydroxyl at position 3/4 is not fundamentally essential for
activity there is less scope for its modification.
3. Conclusion

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In summary, DCI, its enantiomer
L-chiro-inositol, and certain modified analogues of DCI, increased 2-
deoxy-
D
-[2,6-3H]glucose uptake in 3T3-L1 adipocytes confirming that these compounds possess
insulin-like actions. Positional analyses indicate that the 1/6-hydroxyl group of DCI is not essential
for activity and can be modified without detrimentally affecting glucose uptake. Activity was also
unaffected by removal of the 3/4-hydroxyl group. However, this position was sensitive to O-
alkylation but did tolerate esterification. By comparison, the hydroxyl at position 2/5 is essential for
glucose uptake although can be in either an equatorial or axial orientation. Interestingly however, the
2/5-O-butylated-DCI derivative (8) retained some bioactivity implying that O-alkylation at this
position can be tolerated.
From these data it can be concluded that alkylation can be tolerated at position 2 whereas acylation is
better tolerated at position 3 of
D-chiro-inositol. In some contrast, deoxygenation is tolerated at
positions 1 and 3 and not position 2. Taken together it appears a combination of chemical
modifications including alkylation or esterification and deoxygenation offer an attractive scope for the
development of DCI analogues with desirable pharmacokinetic profiles.

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4. Experimental section
4.1. Chemical synthesis
All reactions were performed in oven- and flame-dried glassware under an argon atmosphere. Air and
moisture sensitive reagents and solvents were transferred via syringes or cannula, and they were
introduced into the reaction vessel through a rubber septum. Chemicals obtained from commercial
sources were used without further purification. Flash column chromatography was carried out on
silica gel (230-400 mesh). Analytical thin-layer chromatography (TLC) was performed with silica gel
1
60 F254. NMR spectra were recorded on a Bruker Avance 300 MHz NMR spectrometer and H
13
chemical shifts were expressed in ppm downfield from the internal TMS or D2O (4.78); C NMR
spectra were calibrated with reference to residual CHCl3 (77.00). NMR spectra were ran in CDCl3
unless otherwise stated. 5-Deoxy-
D-chiro-inositol (5; (+)-Quercitol) was purchased from Tokyo
Chemical Industry Ltd. NH3(aqs) means 28% aqueous ammonia.
4.1.1. Synthesis of 6-Deoxy-3-O-methyl-D-chiro-inositol (4) and 6-Deoxy-D-chiro-inositol (3)
(Scheme 1)
6-Deoxy-3-O-methyl-
D-chiro-inositol (4)
1,2:4,5-Di-O-isopropylidene-3-O-methyl-
D
-chiro-inositol 11 [27]
(2.62 g, 9.55 mmol) was stirred in anhydrous THF (25 mL)
under argon and cooled to 0 ºC. Sodium hydride (60% in mineral
oil; 0.57 g, 14.3 mmol) was added in portions and the suspension allowed to warm to room
temperature. After 15 min, the mixture was cooled to 0 ºC and carbon disulfide (688 µL, 11.4 mmol)
was added dropwise. The solution was then stirred for 30 min at room temperature and again cooled
to 0 ºC. Methyl iodide (890 µL, 14.3 mmol) was added and the reaction left at room temperature for
18 h. Solid NaHCO3 (1.27 g, 15.1 mmol, 1.59 eq.) and acetic acid (0.85 mL, 14.8 mmol, 1.56 eq.)
were added and the solvent evaporated. The residue was dissolved in Et2O (30 mL), washed with H2O
(2 x 30 mL), dried (MgSO4) and concentrated in vacuo to give 1,2:4,5-di-O-isopropylidene-3-O-
1
methyl-6-thiomethylester-
D
-chiro-inositol 12 as a yellow solid. H NMR: δ 6.44 (t, J = 2.3 Hz, 1H),
4.41 (dd, J = 5.9, 1.8 Hz, 1H), 4.21 (dd, J = 5.9, 5.9 Hz, 1H), 4.05-3.90 (m, 2H), 3.59 (s, 3H), 3.52
(dd, J = 9.7, 5.9 Hz, 1H), 2.59 (s, 3H), 1.52 (s, 3H), 1.48 (s, 3H), 1.42 (s, 3H), 1.34 (s, 3H); 13C NMR:
δ 215.2, 112.1, 109.8, 84.3, 80.7, 76.6, 75.5, 74.9, 74.4, 58.6, 27.6, 27.1, 26.3, 25.4, 19.2. 2,4,6-
Collidine (3.15 mL, 23.8 mmol) and 2-propanol (50 mL) were added to the crude material and argon
was bubbled through the solution for 30 min. The solution was then heated to reflux and lauroyl
peroxide (5.70 g, 14.3 mmol) was added in portions over 4 h. The solution was heated under reflux
for another 30 min, before being stirred at room temperature overnight. Any residual peroxides
present were quenched with the addition of aqueous Na2SO3 solution (1.2 M, 10 mL), cooled and the
solvent evaporated to give 6-deoxy-1,2:4,5-di-O-isopropylidene-3-O-methyl-d-chiro-inositol 13. The

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crude mixture was dissolved in H2O (16 mL) and trifluoroacetic acid (4 mL) and stirred at room
temperature for 1.5 h. More H2O (20 mL) was added and the mixture was washed with 1:5 mixture of
EtOAc/ petroleum ether (2 x 20 mL). The combined organic layers were washed with H2O (2 x 20
mL) and the combined aqueous extracts concentrated in vacuo. The residue was purified by silica gel
chromatography (75:20:2 CHCl3/MeOH/H2O) to give partially deprotected material (2.52 g) which
was taken forward to the next step, and also a pure sample of 6-deoxy-3-O-methyl-D-chiro-inositol
(4) which spontaneously crystallised after eluting from the column. This material was thus filtered to
afford 4 as colourless needles (341 mg, 1.91 mmol, 20% over 3 steps). mp 145-148 °C, [α] 23 +57.6
D
(c 1.0, H2O); 1H NMR (D2O): δ 4.12 (ddd, J = 4.1, 2.8, 2.4 Hz, 1H), 3.84 (ddd, J = 12.2, 9.0, 4.5 Hz,
1H), 3.65-3.61 (m, 1H), 3.64 (s, 3H), 3.40-3.37 (m, 2H), 2.14 (ddd, J = 14.2, 4.5, 4.1 Hz, 1H), 1.57
(ddd, J = 14.2, 12.2, 2.4 Hz, 1H); 13C NMR (D2O): δ 83.0, 77.1, 73.4, 68.74, 68.65, 60.1, 35.2; HRMS
FAB(-) calcd for C7H14O5: m/z 177.07630 [M-H]- found: 177.07591. Anal. calcd for C7H14O5: C,
47.18; H, 7.92, found: C, 47.02; H, 7.91.

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6-Deoxy-D-chiro-inositol (3) [40]
The partially deprotected material from above (2.52 g) and
hydriodic acid (57 wt % in H2O; 20 mL) were heated at 140 °C
under Dean-Stark conditions for 3 h. The resulting solution was
evaporated, the residue dissolved in water (15 mL) and washed with
EtOAc (2 x 10 mL). The aqueous extract was concentrated in vacuo and purified by silica gel
chromatography (60:35:8 CHCl3/MeOH/NH3(aq)) to give 6-deoxy- -chiro-inositol (507 mg, 3.09
D
mmol, 40% over 4 steps). This product could be crystallised from H2O/EtOH to give colourless
needles which contained 0.5 equivalents of water; mp 185-186 °C (lit.[40] 180-181 °C), [α] 23 +52.8
D
(c 1.0, H2O); 1H NMR (D2O): δ 4.13 (ddd, J = 3.9, 3.0, 2.6 Hz, 1H), 3.83 (ddd, J = 12.1, 9.4, 4.8 Hz,
1H), 3.61 (dd, J = 9.7, 9.1 Hz, 1H), 3.55 (dd, J = 9.7, 3.0 Hz, 1H), 3.32 (dd, J = 9.4, 9.1 Hz, 1H),
2.16 (ddd, J = 14.0, 4.8, 3.9 Hz, 1H), 1.62 (ddd, J = 14.0, 12.1, 2.6 Hz, 1H); 13C NMR (D2O): δ 77.7,
74.0, 73.0, 68.7, 68.6, 35.3; HR ESMS(+) calcd for C6H12O5: m/z 182.10285 [M+NH4]+ found:
182.10379. Anal. calcd for C6H12O5: C, 43.90; H, 7.37, found: C, 43.87; H, 7.41 (after drying at 50ºC
under vacuum).
4.1.2. Synthesis of 4-Deoxy-3-O-methyl-
(Scheme 2)
D-chiro-inositol (14C) [41] and 4-Deoxy-D-chiro-inositol (6)
4-Deoxy-3-O-methyl-D-chiro-inositol (14C)
1,2:5,6-Di-O-isopropylidene-3-O-methyl- -chiro-inositol 14 [27] (2.50 g, 9.11 mmol) was suspended
D
in anhydrous THF (25 mL) under argon and cooled to 0 ºC. Sodium hydride (60% in mineral oil; 0.55
g, 13.7 mmol) was added in portions and the suspension allowed to warm to room temperature. After
30 min, the mixture was cooled to 0 ºC and carbon disulfide (658 µL, 10.9 mmol) was added
dropwise. The solution was stirred for 45 min at room temperature and then again cooled to 0 ºC.
Methyl iodide (850 µL, 13.7 mmol) was added and the reaction left over 48 hrs. Solid NaHCO3 (0.50
g, 5.95 mmol) and acetic acid (0.34 mL, 5.94 mmol) were added and the solvent evaporated. The
residue was dissolved in Et2O (20 mL), washed with H2O (2 x 20 mL), dried (MgSO4) and
concentrated
in
vacuo
to
give
crude
1,2:5,6-di-O-isopropylidene-3-O-methyl-4-O-
[(methylthio)thiocarbonyl]-
D
-chiro-inositol 14C (4.13 g). 1H NMR: δ 6.01 (dd, J = 10.9, 7.4 Hz, 1H),
4.46-4.40 (m, 3H), 4.30 (dd, J = 7.5, 5.7 Hz, 1H), 3.51 (s, 3H), 3.38 (dd, J = 10.9, 7.4 Hz, 1H), 2.61 (s,
3H), 1.53 (s, 3H), 1.52 (s, 3H), 1.37 (s, 3H), 1.34 (s, 3H); 13C NMR: δ 216.3, 109.8, 109.3, 81.2, 80.7,
78.3, 76.4, 75.5, 75.3, 60.3, 27.8, 27.4, 25.5, 25.3, 19.3.
Collidine (3.0 mL, 22.8 mmol) and 2-propanol (50 mL) was added to the crude material (1.32 g) and
argon was bubbled through the solution for 20 min. The solution was then heated under reflux and
lauroyl peroxide (4.73 g, 13.7 mmol) was added in portions over 4 h. The solution was heated under
reflux for another 30 min and cooled before quenching any peroxides present with aqueous Na2SO3

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solution (1.5 M, 5 mL). The solvent was removed in vacuo and the residue dissolved in EtOAc (15
mL), washed with saturated aqueous NaHCO3 (2 x 10 mL), aqueous HCl (2M, 2 x 10 mL), H2O (10
mL), dried (MgSO4) and the solvent evaporated to give 4-deoxy-1,2:5,6-di-O-isopropylidene-3-O-
methyl- -chiro-inositol (14b) as a yellow oil.
D
Trifluoroacetic acid (4 mL) and H2O (16 mL) were added and the
mixture stirred at RT for 1.5 hrs. More H2O (20 mL) was added
and the mixture was washed with petroleum ether (10 mL). The
organic layer was extracted with H2O (2 x 10 mL) and the
combined aqueous extracts concentrated in vacuo. The residue was purified by silica gel
chromatography (75:20:2 CHCl3/MeOH/H2O) to give 4-deoxy-3-O-methyl-D-chiro-inositol (14c) as a
colourless oil (478 mg, 2.68 mmol, 92% over 3 steps); [α] 23 +74.1 (c 1.1, H2O); 1H NMR (D2O): δ
D
3.97 (ddd, J = 11.0, 4.0, 3.5 Hz, 1H), 4.04 (dd, J = 3.4, 3.3 Hz, 1H), 3.98 (dd, J = 3.5, 4.5 Hz, 1H),
3.83 (dd, J = 9.0, 3.3 Hz, 1H), 3.56 (ddd, J = 10.5, 9.0, 4.5 Hz, 1H), 3.48 (s, 3H), 2.23 (ddd, J = 12.4,
13
4.5, 4.0 Hz, 1H), 1.68 (ddd, J = 12.4, 11.0, 10.5 Hz, 1H); C NMR (D2O): δ 77.9, 72.1, 72.0, 71.1,
66.7, 56.8, 30.4; HRMS FAB(-) calcd for C7H14O5: m/z 177.07630 [M-H]- found: 177.07597. Anal.
calcd for C7H14O5.0.25H2O: C, 46.02; H, 8.00, found: C, 46.01; H, 8.16.

ACCEPTED MANUSCRIPT
4-Deoxy-
D-chiro-inositol (6) [41] [42]
4-Deoxy-3-O-methyl-
D
-chiro-inositol (478 mg) (14c) was
dissolved in hydriodic acid (57 wt % in H2O; 10 mL) and heated
under Dean-Stark conditions for 3 h. The resulting solution was
evaporated, the residue dissolved in H2O (10 mL) and washed with EtOAc (2 x 10 mL). The aqueous
extract was concentrated in vacuo and purified by silica gel chromatography (60:35:8
CHCl3/MeOH/NH3(aq)) to give 3-deoxy- -chiro-inositol (422 mg, 2.57 mmol, 88% over 4 steps) as a
D
white solid. This product could be crystallised from H2O/EtOH; mp 262-263 °C [42] (254-255 °C),
[α] 24 +33.6 (c 0.9, H2O); 1H NMR (D2O): δ 4.10-4.04 (m, 2H), , 3.97 (dd, J = 3.4, 3.3 Hz, 1H), 3.84
D
(ddd, J = 9.0, 10.3, 4.5 Hz, 1H), 3.73 (dd, J = 9.0, 3.3 Hz, 1H), 2.05 (ddd, J = 12.2, 4.5, 4.3 Hz, 1H),
1.77 (ddd, J = 12.2, 11.4, 10.3 Hz, 1H); 13C NMR (D2O): δ 72.6, 72.3, 72.1, 68.3, 66.8, 33.9; HRMS
FAB(-) calcd for C6H12O5: m/z 163.06065 [M-H]- found: 163.06069. Anal. calcd for C6H12O5: C,
43.90; H, 7.37, found: C, 43.71; H, 7.60.
4.1.3. Synthesis of 1-O-Butyl-
D-chiro-inositol (7)
(2`R,3`R)-2,3:4,5-Bis-O-(2`,3`-dimethoxybutane-2`,3`-diyl)-
D
-chiro-inositol 15 [30] (2.05 g, 5.02
mmol) was dissolved in anhydrous DMF (10 mL) and the solution cooled to 0 ºC. Sodium hydride
(60% in mineral oil; 402 mg, 10.0 mmol) was added and the reaction stirred at room temperature for
10 min. The reaction was again cooled to 0 ºC, 1-iodobutane (633 µL, 5.52 mmol) was added and the
reaction left to warm to room temperature overnight. A second aliquot of 1-iodobutane (633 µL, 5.52
mmol) was added and the reaction stirred for a further 6 days. The reaction was quenched with
methanol (1 mL), the solvent removed in vacuo and the residue purified by silica gel chromatography
(1:9 EtOAc/petroleum ether) to give the di-alkylated material 1,6-di-O-butyl-(2`R,3`R)-2,3:4,5-bis-O-
(2`,3`-dimethoxybutane-2`,3`-diyl)-
EtOAc/petroleum ether) afforded 1-butyl-(2`R,3`R)-2,3:4,5-bis-O-(2`,3`-dimethoxybutane-2`,3`-diyl)-
-chiro-inositol 16 (563 mg, 1.21 mmol, 24%). This compound was then dissolved in H2O (5 mL) and
D
-chiro-inositol (316 mg, 0.61 mmol, 12%). Further elution (3:7
D
trifluoroacetic acid (5 mL) and stirred at room temperature for 18 h. The product mixture was then
concentrated in vacuo and the residue purified by silica gel chromatography (75:20:2
CHCl3/MeOH/H2O) to give 1-O-butyl- -chiro-inositol 7 as a colourless solid (254 mg, 1.08 mmol,
D
89%); mp 124-125 ºC, [α] 23 +56.5 (c 1.0, H2O); 1H NMR (D2O): δ 4.22 (dd, J
D
= 3.5, 3.4 Hz, 1H), 3.84-3.58 (m, 7H), 1.66-1.56 (m, 2H), 1.46-1.33 (m, 2H),
13
0.95 (t, J = 7.4 Hz, 3H); C NMR (D2O): δ 80.1, 73.5, 73.0, 71.6, 71.1, 70.6,
69.3, 31.6, 19.0, 13.5; HRMS FAB(-) calcd for C10H20O6: m/z 235.11816 [M-H]- found: 235.11855.
Anal. calcd for C10H20O6.0.5H2O: C, 48.97; H, 8.63, found: C, 49.05; H, 8.26.

ACCEPTED MANUSCRIPT
4.1.4. Synthesis of 2-O-Butyl-
D-chiro-inositol (8) (Scheme 4)
2-O-Butyl-3,4-di-O-benzyl-D-chiro-inositol (18)
3,4-Di-O-benzyl- -chiro-inositol 17 [30] (222 mg, 0.62 mmol) and dibutyltin
D
oxide (322 mg, 1.29 mmol) in toluene (5 mL) were heated under reflux for 30
min. The resulting solution was concentrated in vacuo and the residue dissolved
in anhydrous DMF (5 mL) at 100 ºC. 1-Iodobutane (77.0 µL, 0.68 mmol) and
cesium fluoride (9 mg, 0.06 mmol) were added and the mixture heated at 100 ºC for 24 h. More 1-
iodobutane (77.0 µL, 0.68 mmol) was added and heating continued for another 3 days. The mixture
was concentrated in vacuo and the residue purified by silica gel chromatography (49:1 CHCl3/MeOH)
to give a product containing fraction which was further purified by a second column (3:1
EtOAc/petroleum ether) to give 2-O-butyl-3,4-di-O-benzyl- -chiro-inositol 18 as a colourless oil (74
D
1
mg, 0.18 mmol, 29%). H NMR: δ 7.38-7.27 (m, 10H), 4.98 (d, J = 11.5 Hz, 1H), 4.90 (d, J = 11.1
Hz, 1H), 4.77 (d, J = 11.1 Hz, 1H), 4.64 (d, J = 11.5 Hz, 1H), 4.15-4.08 (m, 2H), 3.88 (dd, J =9.1, 2.4
Hz, 1H), 3.77-3.62 (m, 5H), 1.64-1.54 (m, 2H), 1.44-1.32 (m, 2H), 0.91 (t, J = 7.3, 3H); 13C NMR: δ
138.7, 138.6, 128.6 (2 x CH), 128.4 (2 x CH), 127.9 (5 x CH), 127.6, 81.3, 81.0, 80.7, 75.4, 75.3,
70.9, 70.7, 70.5, 68.9, 32.3, 19.3, 13.9.
2-O-Butyl-
D-chiro-inositol (8)
2-O-Butyl-3,4-di-O-benzyl-
D
-chiro-inositol (18) (264 mg, 0.64 mmol) and
Pd(OH)2 on carbon (ca. 20% Pd; 100 mg) in tert-butanol (5 mL) were stirred under
H2 at atmospheric pressure overnight. The mixture was filtered through Celite, the
residue washed with MeOH and the combined filtrates concentrated in vacuo.
Purification by silica gel chromatography (75:20:2 CHCl3/MeOH/H2O) afforded 2-O-butyl-
D
-chiro-
inositol as a colourless foam (136 mg, 0.58 mmol, 92%); [α] 23 +73.6 (c 1.0, H2O); 1H NMR (D2O):
D
δ 4.26 (dd, J = 3.6, 3.5 Hz, 1H), 4.09 (dd, J = 3.6, 3.6 Hz, 1H), 3.83-3.71 (m, 2H) 3.68-3.52 (m, 4H),
1.64 (tt, J = 7.2, 6.8 Hz, 2H), 1.43 (qt, J = 7.4, 7.2 Hz, 2H), 0.96 (t, J = 7.4 Hz, 3H); 13C NMR (D2O):
δ 79.0, 73.3, 72.3, 71.9, 70.8, 70.4, 68.6, 31.5, 19.0, 13.5; HRMS FAB(-) calcd for C10H20O6: m/z
235.11816 [M-H]- found: 235.11766. Anal. calcd for C10H20O6: C, 50.84; H, 8.53, found: C, 50.83; H,
8.51.
4.1.5. Synthesis of 3-O-Butyl-
D-chiro-inositol (9) (Scheme 5)
3-O-Butyl-1,2:5,6-Di-O-isopropylidene-
D-chiro-inositol (20)

ACCEPTED MANUSCRIPT
1,2:5,6-Di-O-isopropylidene-
D
-chiro-inositol 19 [33, 34] [30] (1.22 g, 4.69 mmol)
was dissolved in anhydrous DMF (10 mL) and the solution cooled to 0 ºC. Sodium
hydride (60% in mineral oil; 206 mg, 5.16 mmol) was added and the reaction stirred
at room temperature for 30 min. The reaction was again cooled to 0 ºC, 1-
iodobutane (589 µL, 5.16 mmol) added and the reaction left to warm to room
temperature overnight. The reaction was concentrated in vacuo and the residue purified by silica gel
chromatography (1:4 EtOAc/petroleum ether) to give 3-O-butyl-1,2:5,6-di-O-isopropylidene- -chiro-
D
1
inositol as colourless needles (745 mg, 2.35 mmol, 50%); mp 93-94 °C, H NMR: δ 4.26-4.16 (m,
4H), 3.89 (dt, J = 9.4, 6.6 Hz, 1H), 3.61-3.58 (m, 1H), 3.55 (dt, J = 9.4, 6.6 Hz, 1H), 3.27 (dd, J =
11.2, 6.2 Hz, 1H), 2.94 (d, J = 0.7 Hz, 1H), 1.61 (tt, J = 6.8, 6.6 Hz, 2H), 1.51 (s, 6H), 1.40 (qt, J =
13
7.4, 6.8 Hz, 2H), 1.35 (s, 3H), 1.34 (s, 3H), 0.94 (t, J = 7.4 Hz, 3H); C NMR: δ 110.4, 110.1, 80.2,
79.6, 78.8, 77.5, 77.1, 71.7, 71.5, 32.3, 28.1, 28.0, 25.6, 25.4, 19.6, 14.2.
3-O-Butyl-
D-chiro-inositol (9)
3-O-Butyl-1,2:5,6-di-O-isopropylidene-
D
-chiro-inositol (478 mg, 1.51 mmol)
was left stirring overnight in CH2Cl2 (4.5 mL) and trifluoroacetic acid (0.5 mL)
and then concentrated in vacuo. The residue was purified by silica gel
chromatography (60:30:8 CHCl3/MeOH/NH3(aq)) and then passed through a
Dowex 50W 8-200 (H+ form) ion exchange column to remove ammonium trifluoroacetate yielding 3-
O-butyl-
D
-chiro-inositol 9 as a colourless solid (299 mg, 1.27 mmol, 84%); mp 148 ºC, [α] 22 +53.0
D
(c 1.1, H2O); 1H NMR (D2O): δ 4.07-4.04 (m, 2H), 3.84 (t, J = 6.9 Hz, 2H), 3.87-3.79 (m, 2H), 3.68
(dd, J = 9.6, 9.6, 1H), 3.47 (dd, J = 9.6, 9.6 Hz, 1H), 1.65 (tt, J = 7.4, 6.9 Hz, 2H), 1.42 (qt, J = 7.4,
7.4 Hz, 2H), 0.96 (t, J = 7.4 Hz, 3H); 13C NMR (D2O): δ 81.8, 73.3, 72.7, 72.2, 71.9, 71.0, 70.4, 31.9,
19.0, 13.6; HRMS FAB(-) calcd for C10H20O6: m/z 235.11816 [M-H]- found: 235.11716. Anal. calcd
for C10H20O6: C, 50.84; H, 8.53, found: C, 50.79; H, 8.57.

ACCEPTED MANUSCRIPT
4.1.6 Synthesis of 3-O-Butanoyl-
D-chiro-inositol (10) (Scheme 5)
1,2:5,6-Di-O-isopropylidene- -chiro-inositol (1.00 g, 3.85 mmol) was
D
dissolved in anhydrous pyridine (5 mL) and the solution cooled to 0 ºC.
Butyryl chloride (600 µL, 5.78 mmol) was added dropwise and the reaction
stirred at room temperature for 3 h. The reaction was again cooled to 0 ºC,
more butyryl chloride (400 µL, 3.85 mmol, 1.0 eq.) added and the reaction
left to warm to room temperature over 18 h. The reaction was concentrated in
vacuo to give crude 3-O-butanoyl-1,2:5,6-di-O-isopropylidene- -chiro-inositol
D
21. This material was then stirred at room temperature in a mixture of CH2Cl2
(10 mL) and trifluoroacetic acid (15 mL) overnight. The product mixture was
then concentrated in vacuo and the residue filtered through a Dowex 50X8-200 (H+ form) ion
exchange column eluting with H2O. The resulting product was purified by silica gel chromatography
(75:20:2 CHCl3/MeOH/H2O) to give 3-O-butanoyl- -chiro-inositol 10 (739 mg, 2.95 mmol, 77%
D
over 2 steps) which could be recrystallized from MeOH/acetone to give colourless needles; mp 142-
144 ºC, [α] 23 +64.0 (c 1.3, H2O); H NMR (D2O): δ 5.13 (dd, J = 10.1, 9.4 Hz, 1H), 4.13-4.09 (m,
1
D
2H), 3.97 (dd, J = 10.1, 2.4 Hz, 1H), 3.89 (dd, J = 10.0, 2.3 Hz, 1H), 3.78 (dd, J = 10.0, 9.4 Hz, 1H),
13
2.51 (t, J = 7.3 Hz, 2H), 1.72 (qt, J = 7.4, 7.3 Hz, 2H), 1.00 (t, J = 7.4 Hz, 3H); C NMR (D2O): δ
177.0, 75.4, 72.2, 71.8, 71.2, 70.8, 69.1, 36.4, 18.4, 13.2; HRMS FAB(-) calcd for C10H18O7: m/z
249.09743 [M-H]- found: 249.09692. Anal. calcd for C10H18O7: C, 48.00; H, 7.25, found: C, 47.74; H,
7.26.
4.2. Glucose uptake in 3T3-L1 adipocytes
3T3-L1 fibroblasts were sub-cultured to passage nine in DMEM supplemented with 0.11 g/L sodium
pyruvate and L-glutamine, 10% fetal bovine serum, 100 U/mL penicillin-G, and 95 µg/mL
streptomycin sulphate. Cells were seeded into 6-well plates and then maintained at 5% CO2 and 37 ºC
until confluent. Differentiation of 3T3-L1 fibroblasts was induced following incubation with 0.5 mM
IBMX, 0.25 µM dexamethasone, and 10 µg/mL insulin for 8 days. Approximately 90% differentiation
was observed as indicated by a change in morphology characterised by the presence of large
intracellular lipid droplets are using light microscopy [43].
3T3-L1 adipocytes were washed twice with serum free media (10 min incubation), then incubated
with serum free media for 1 h and washed with KRB buffer. Glucose uptake was measured by adding
900 µL of KRB buffer and then 50 µL of KRB buffer containing either insulin (100 nM final
concentration) or the selected inositol compound (200 µM final concentration). 50µl of 2-deoxy-
D-
[2,6-3H]glucose was added (5 mCi, 53 Ci/mmol, 1.96 Bq/mmol, Amersham Biosciences batch #

ACCEPTED MANUSCRIPT
TRK672) to give a final concentration of 0.5 Ci (9.4 µM). Following incubation cells were washed 3
times with chilled phosphate buffered saline and solubilised in 1 mL of 0.5 M sodium hydroxide and
1% (w/v) sodium dodecyl sulphate. Following the addition of Starscint scintillation fluid (Packard,
cat# 6013248) to each sample (2:1 v/v) radioactivity was measured in a liquid scintillation counter
(LKB Wallac 1450 Micorbeta plus, PerkinElmer, Inc.).
For each individual experiment, 2-deoxy-D
-[2,6-3H]glucose uptake was compared between the basal
state, in the presence of the selected inositol compound, and in the presence of insulin. Individual
wells were randomly selected for each treatment and the number of replicates were statistically
powered to detect a 20% difference over basal uptake with a p<0.05. Statistical analyses were
performed using one-way ANOVA followed by Tukey’s post-hoc test using the software algorithms
provided by GraphPad Prism 5.0. Inositol compounds were screened once if a positive stimulatory
effect on 2-deoxy-
was observed.
D
-[2,6-3H]glucose was observed and independently screened twice if no stimulation
4.3. Single crystal X-ray studies of 3-O-butanoyl-D-chiro-inositol (10)
The single crystal X-ray diffraction data were recorded using ω scans on an Agilent SuperNova Dual
Source diffractometer with an EosS2 CCD detector using mirror-collimated CuKα radiation
(λ = 1.54184 Å). The intensity data were collected with an average fivefold redundancy per reflection.
The intensity data collection, frames integration and numerical absorption correction (gaussian) were
performed using CrysAlisPro [44]. The structure was solved by direct methods using the SHELXS-97
program and refined by full-matrix least-squares using SHELXL-2014 [45]. The non-hydrogen atoms
were refined with anisotropic displacement parameters. All hydrogen atoms were refined as riding,
with Uiso = 1.2Ueq of the parent atoms, except for oxygen-bound hydrogen atoms where Uiso was
freely refined (AFIX 143). The Flack parameter (x = -0.07(10)) indicates refinement was carried out
using the correct absolute configuration.
Acknowledgements.
This research was supported through Science funding support from FRST (C08X0209) and
Technology New Zealand.
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Legends.
Figure 1. Structures of D-chiro-inositol (1) and L-chiro-inositol (2).
Figure 2. ORTEP view (50% probability level) of the molecular structure of 3-O-butanoyl-D-chiro-
inositol (10).
Figure 3. Insulin and inositol stimulated 2-deoxy-
Comparison of the basal (ꢀ) and insulin induced (ꢁ) uptake of 2-deoxy-
point represents mean ± SEM (n=4). (B) Stimulation 2-deoxy-
-[2,6-3H]glucose uptake by DCI. Data
show one experiment from three independent experiments. Data shown as mean ± SEM for basal
(n=5), DCI (n=15), and insulin (n=6). (C) Stimulation of 2-deoxy-
-[2,6-3H]glucose uptake by
chiro-inositol. Data shows one experiment from two independent experiments. Data shown as mean ±
SEM for basal (n=15), -chiro-inositol (n=15), and insulin (n=6).
D
-[2,6-3H]glucose uptake in 3T3-L1 adipocytes. (A)
-[2,6-3H]glucose. Each
D
D
D
L-
L
Figure 4. Schematic of the modified analogues of DCI synthesised and tested. All compounds were
screened using the same experimental conditions and at the same concentration as that for -chiro-
D
inositol (200 µM). A lack of any significant stimulation is indicated by a dash. Significant stimulation
+
is indicated by +. <20%; ++20-39%; +++40-59%; ++++60-80% of the insulin response. The symbol, -
represents no significant effect. The symbol, *, represents inhibition.
Table 1. Crystal data and structure refinement for 3-O-butanoyl-
D-chiro-inositol (10).
Table 2. Insulin and inositol stimulated 2-deoxy-
D
-[2,6-3H]glucose uptake in 3T3-L1 adipocytes.
Scheme 1. Synthesis of 6-deoxy-3-O-methyl-D-chiro-inositol 4 and 1-deoxy-D-chiro-inositol 3.
(a) NaH, CS2, MeI, THF; (b) collidine, lauroyl peroxide, 2-propanol; (c) TFA, H2O, 20% over 3 steps;
(d) HI, 40% over 4 steps.
Scheme 2. Synthesis of 4-deoxy-D-chiro-inositol 6. Conditions as detailed in Scheme 1; (d) 88% over
4 steps.
Scheme 3. Synthesis of 1-O-butyl-
Scheme 4. Synthesis of 2-O-butyl-
D
D
-chiro-inositol 7. (e) NaH, BuI, DMF, 24%; (c) TFA, H2O, 89%.
-chiro-inositol 8. (f) Bu2SnO, toluene then BuI, CsF, DMF, 29%;
(g) H2, Pd(OH)2/C, t-BuOH, 92%.

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Scheme 5. Synthesis of 3-O-butyl-D-chiro-inositol 9 and 3-O-butanoyl-D-chiro-inositol 10. (e) NaH,
BuI, DMF, 50%; (i) 84% for compound 9. (h) Butyryl chloride, pyridine; (i) TFA, CH2Cl2, 77% over
two steps for compound 10.

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Figures.
Figure 1.

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Figure 2.

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Figure 3.

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Figure 4.

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Table 1. Crystal data and structure refinement for 3-O-butanoyl- -chiro-inositol (10).
D
3-O-Butanoyl-
1475086
D-chiro-inositol
Parameters
CCDC
Empirical formula
Formula weight
Temperature
C10H18O7
250.25
120(2) K
1.54184 Å
Wavelength
Crystal system, space group
Orthorhombic, P212121
a = 6.6480(1)
Unit cell dimensions
b = 7.6589(2)
c = 22.8652(5)
1164.21(4) Å3
4, 1.428 Mg/m3
1.044 mm−1
Volume
Z, Calculated density
Absorption coefficient
F(000)
536
Crystal size
0.147 × 0.038 × 0.034 mm
Theta range for data collection 6.094 to 71.714 deg.
Limiting indices
−8 ≤ h ≤ 8,−9 ≤ k ≤ 9, −24 ≤ l ≤ 28
Reflections collected/unique
11314/2272 [R(int) = 0.0632]
Completeness to theta = 67.684 99.9%
Absorption correction
Max. and min. transmission
Refinement method
Numerical (gaussian)
0.977 and 0.992
Full-matrix least-squares on F2
2272/0/160
Data/restraints/parameters
Goodness-of-fit on F2
1.039
Final R indices [I > 2sigma(I)] R1 = 0.0297, wR2 = 0.0749
R indices (all data)
R1 = 0.0309, wR2 = 0.0759
0.176 and −0.196 e.A−3
Largest diff. peak and hole

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Table 2. Insulin and inositol stimulated 2-deoxy-
D
-[2,6-3H]glucose uptake in 3T3-L1 adipocytes.
FOLD-OVER BASAL (mean ± SEM,
(number independent experiments))
2-DG UPTAKE (cpm/60 min) (mean ± SEM)
% of Insulin
response
Compound (200 µM)
Insulin (100 nM)
Compound
-chiro-inositol (1)
-chiro-inositol (2)
Exp
Basal
Compound
Insulin
1.4 ± 0.2
2.8 ± 0.3
1.8 ± 0.3
3.5 ± 1.4
D
1
2
103 ± 15 (n=10)
171 ± 12 (n=15)
148 ± 6.5 (n=10)*
478 ± 29 (n=15)**
185 ± 10 (n=4)**
593 ± 243 (n=6)**
64 ± 9 (2)
L
2
3
1
1
2
1
2
1
1
2
1
1
2
1
2
399 ± 23 (n=15)
246 ± 20 (n=15)
475 ± 32 (n=15)
193 ± 13 (n=15)
4798 ± 222 (n=14)
471 ± 17 (n=15)
753 ± 48 (n=15)
571 ± 39 (n=15)
3326 ± 127(n=15)
1341 ± 77 (n=15)
708 ± 35 (n=15)
1633 ± 78 (n=15)
1537 ± 67 (n=9)
627 ± 36 (n=15)
1845 ± 68 (n=15)
585 ± 41 (n=15)**
735 ± 32 (n=15)****
617 ± 28 (n=15)**
162 ± 21 (n=15)
5640 ± 359 (n=15)
234 ±57 (n=15)***
770 ± 25 (n=15)
731 ± 20 (n=15)**
4585 ± 222 (n=15)*
1954 ± 60 (n=15) **
956± 46 (n=15)**
1890 ± 78 (n=15)
1715 ± 61 (n=11)
805 ± 31 (n=15)*
1648 ± 60 (n=15)
818 ± 103 ( n=6)****
1414 ± 50.0 (n=15)****
1132 ± 29 (n=6)****
1015 ± 33 (n=6)****
16378 ± 365 (n=6)****
694 ± 34 (n=6)**
1179 ± 42 (n=6)****
969 ± 36 (n=6)****
19799 ± 1088 (n=6)**** 1.4 ± 0.1
8660 ± 496 (n=6)****
1827 ± 185 (n=6)****
8163 ± 293 (n=6)****
4847 ± 394 (n=4)****
1578 ± 169 (n=6)****
14471 ± 840 (n=6)****
1.5 ± 0.1
3.0 ± 0.3
1.3 ± 0.1
NS
NS
0.50 ± 0.1
NS
2.1 ± 0.3
5.7 ± 0.5
2.4 ± 0.2
5.3 ± 0.4
3.4 ± 0.2
1.5 ± 0.1
1.6 ± 0.1
1.7 ± 0.1
6.0 ± 0.4
6.5 ± 0.5
2.6 ± 0.3
5.0 ± 0.3
3.2 ± 0.3
2.5 ± 0.3
7.8 ± 0.5
43 ± 1 (2)
22 ± 7 (1)
-
6-Deoxy-DCI (3)
6-Deoxy-3-O- methyl-
DCI (4)
-106 ± 32 (1)
5-Deoxy-DCI (5)
4-Deoxy-DCI (6)
1-O-Butyl-DCI (7)
2-O-Butyl-DCI (8)
3-O-Butyl-DCI (9)
1.3 ± 0.1
40 ± 12 (1)
8.0 ± 0.3 (2)
22 ± 8 (1)
-
1.5 ± 0.1
1.4 ± 0.1
NS
NS
1.3 ± 0.1?
NS
3-O-Butanoyl-DCI (10)
19 ± 6 (1)
**** = P < 0.0001 vs. basal
*** = P < 0.001 vs. basal
** = P < 0.01 vs. basal
* = P < 0.05 vs. basal

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Scheme 1.