Synthesis, characterization and antitumor activity of some arylantimony triphenylgermanylpropionates and crystal structures of Ph3GeCH(Ph)CH2CO2SbPh4 and [Ph3GeCH2CH(CH3)CO2] 2Sb(4-ClC6H4)3

Article abstract of DOI:10.1016/S0022-328X(00)00799-3

A series of novel arylantimony(V) triphenylgermanylpropionates with the formula (Ph₃GeCHR¹CHR²CO₂) _nSbAr_(5-n) (R¹ = H, Ph; R² = H, CH₃; n = 1, 2) were synthesized and characterized by elemental analysis, IR, ¹H-NMR, ¹³C-NMR and mass spectroscopy. The crystal structures of Ph₃GeCH(Ph)CH₂CO₂SbPh₄ and [Ph₃GeCH₂CH(CH₃)CO₂] ₂Sb(4-ClC₆H₄)₃ were determined by X-ray diffraction. The in vitro antitumor activities of some selected compounds against five cancer cells are reported.

Full text of DOI:10.1016/S0022-328X(00)00799-3

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Journal of Organometallic Chemistry 620 (2001) 235–242
Synthesis, characterization and antitumor activity of some
arylantimony triphenylgermanylpropionates and crystal structures
of Ph3GeCH(Ph)CH2CO2SbPh4 and
[Ph3GeCH2CH(CH3)CO2]2Sb(4-ClC6H4)3
Yongqiang Ma *, Jinshan Li, Zhenai Xuan, Runchang Liu
National Laboratory of Elemento-Organic Chemistry, Nankai Uni6ersity, Tianjin 300071, People’s Republic of China
Received 6 July 2000; received in revised form 16 October 2000; accepted 16 October 2000
Abstract
A series of novel arylantimony(V) triphenylgermanylpropionates with the formula (Ph3GeCHR1CHR2CO2)nSbAr(5−n) (R1=H,
Ph; R2=H, CH3; n=1, 2) were synthesized and characterized by elemental analysis, IR, 1H-NMR, 13C-NMR and mass
spectroscopy. The crystal structures of Ph3GeCH(Ph)CH2CO2SbPh4 and [Ph3GeCH2CH(CH3)CO2]2Sb(4-ClC6H4)3 were deter-
mined by X-ray diffraction. The in vitro antitumor activities of some selected compounds against five cancer cells are reported.
© 2001 Elsevier Science B.V. All rights reserved.
Keywords: Antimony; Germanium; Crystal structures; Antitumor activity
These arylantimony triphenylgermanylpropionates
were synthesized by the reaction of triphenylgermanyl-
propionic acid with ArnSbBr(5−n) in the presence of
triethylamine. The general reaction scheme is shown as
follows:
1. Introduction
A substantial number of references describing synthe-
sis and applications of RnSbX5−n (R=alkyl, aryl; X=
carboxylate; n=3, 4) have appeared in the literature
[1–20]. To the biological activity of some organoanti-
mony carboxylates Bajpai and co-workers [2] consid-
ered that the activity was not significantly affected by
the nature of the R groups at Sb. However, Singhal and
co-workers [3] found that the effect of the nature of R
groups on the activity was relatively complex. As we
know very well, organogermanium has a wide range of
biological activities [21–24]. Therefore, we have pre-
pared nine new arylantimony b-triphenylgermanylpro-
pionates in order to examine whether including
organogermanium in organoantimony compounds im-
proves their antitumor properties and to investigate the
influence of the organic ligands at Sb on their biological
activity. At the same time we were also interested in
studying the nature of bonding and structure of these
compounds.
Ph3GeCHR1CHR2CO2H
Et N
3
+R3(5−n)SbBrn “ R3(5−n)Sb(O2CCHR2CHR1GePh3)n
For compounds I: n=1, R3=Ph, R1=R2=H (I1);
R1=H, R2=CH3 (I2); R1=Ph, R2=H (I3). For com-
pounds II: n=2, R1=H, R2=CH3, R3=4-CH3C6H4
(II1); 4-ClC6H4 (II2); R1=Ph, R2=H, R3=4-ClC6H4
(II3); Ph (II4); 3-CH3C6H4 (II5); R1=R2=H, R3=Ph
(II6).
2. Results and discussion
2.1. Preparations
The compounds are prepared under mild condition.
All compounds are white crystals and stable under
ordinary conditions. They are easily soluble in organic
* Corresponding author.
E-mail address: llma@eyou.com (Y. Ma).
0022-328X/01/$ - see front matter © 2001 Elsevier Science B.V. All rights reserved.
PII: S0022-328X(00)00799-3

236
Y. Ma et al. / Journal of Organometallic Chemistry 620 (2001) 235–242
solvents such as benzene, toluene, chloroform, and
dimethyl sulfoxide, but not soluble in acetone, ether,
methanol, ethanol, and petroleum ether.
wsym(CO2) between 1377 and 1291 cm−1. On the basis
of the difference Dw(CO2) these compounds can be
divided into two classes: Compounds I1, II2 and II6
The reaction of triarylantimony dichloride with aryl-
magnesium bromide represents a satisfactory method of
preparation of salts such as tetraphenylstibonium bro-
mide. We use toluene instead of benzene and less ether
than in the Ref. [4]. The product was precipitated
during this period, whereas in Ref. [4] that is in solution
as ether–benzene. However, this method has been
proved to be unsatisfactory for the preparation of
quaternary stibonium salts having two or more differ-
ent aryl groups bonded to antimony, mainly because of
the occurrence of exchange reactions between the Grig-
nard reagent and tetraarylstibonium cation.
show low Dw(CO2) values (280, 271 and 283 cm−1
,
respectively) while all other compounds show high
Dw(CO2) values (between 310 and 349 cm−1). To the
former we can assume that there are stronger interac-
tions between the carbonyl oxygen atoms of the car-
boxylate groups and the antimony atom (confirmed by
crystal structure of compound II2). To the latter we can
assume that there are weaker interactions or no interac-
tion between the antimony atom and the carbonyl
oxygen atoms of the carboxylate groups. (See the crys-
tal structure of compound I3). In addition, the frequen-
cies wasy(Sb–C) appear between 458 and 472 cm−1, this
is consistent with the literature [8].
2.2. IR
1
2.3. H-NMR
The IR spectra of these compounds have been
recorded in the range of 4000–400 cm−1. The absorp-
tion bands can be assigned on the basis of earlier
publications and the important data are listed in Table
1.
1
The H-NMR data of the title compounds are listed
in Table 2. The 13C-NMR data of the three compounds
are given in Table 3. From the Table 2 we find when
one b proton is substituted with a phenyl group there is
a significant downfielding shift for a and b protons due
to the deshielding effects. C(1) is a chiral center and
C(2) is a prochiral center. The three hydrogens on C(1)
and C(2) comprise an ABX system. However, the ABX
system can not be identified in 90 MHz spectra. Here
the three hydrogens show a multiplet in most cases. All
the protons in the compounds have been identified and
the total number of protons calculated from the inte-
gration curve tallies with what was expected from the
molecular formula.
The IR spectroscopic data provide further support
for the molecular constitution of the title compounds.
In majority of organoantimony(V) compounds the anti-
mony has generally a coordination number of five.
Because the vacant 5d orbital of antimony atom can
accept lone electron pairs of ligands, in some cases the
antimony may have a coordination number of six [5,6]
or seven [7]. The IR stretching vibration frequencies of
carbonyl groups in organoantimony carboxylates are
very important for determining their structures: When
there are interactions between the antimony atom and
the carbonyl oxygen atoms of the carboxylate groups,
the asymmetric absorption vibration frequencies
[wasy(CO2)] of carbonyl groups decrease and the sym-
metric absorption vibration frequencies [wsym(CO2)] in-
crease.Therefore their differences [Dw(CO2)] decrease
[3,8,9]. In the IR spectra of the title compounds the
carboxylate bands are observed in the characteristic
regions: wasy(CO2) between 1670 and 1622 cm−1 and
2.4. Mass spectra
The main mass spectra data of compound I3 and II6
are listed in Table 4. For both there is no molecular ion
peak. But the fragment ions found are in agreement
with the expected structure of the compounds. Decar-
boxylation and dephenylation from metal atom are the
main breakdown patterns for the two compounds.
2.5. Crystal structure
Table 1
IR data of the compounds (cm−1
)
2.5.1. Structure of Ph3GeCH(Ph)CH2CO2SbPh4
Compound
wasy(CO2)
wsym(CO2)
Dw(CO2
wasy(Sb–C)
A colorless crystal was recrystallized from CH2Cl2–
CH3OH. One of the approximate dimensions 0.30×
0.25×0.20 mm was mounted in a glass capillary and
used for data collection. Fig. 1 shows the molecular
structure of compound I3 and gives the atom number-
ing scheme. The selected bond distances and angles are
listed in Table 5. The Ge–C bonds are consistent with
the literature [25]. The stereochemistry of germanium is
typically tetrahedral geometry. As usual (see Table 6)
I1
I2
I3
II1
II2
II3
II4
II5
II6
1627
1635
1636
1662
1610
1649
1645
1648
1645
1347
1306
1326
1341
1339
1329
1291
1335
1362
280
329
310
321
271
320
349
313
283
466
462
466
466
472
467
458
465
462
,
the apical Sb–C distance (2.151 A) is longer than the

Y. Ma et al. / Journal of Organometallic Chemistry 620 (2001) 235–242
237
Table 2
1H-NMR data of the compounds
Compound GeCHR1
CHR2CO
Ph3Ge
R1
R2
R3
I1
I2
1.42–1.62(2H,t) 2.08–2.24
7.40–7.80
(15H,m)
7.31–7.78
(15H,m)
7.40–7.80 (20H,m)
(2H,t)
1.18
2.15–2.52
(1H,m)
0.68–0.77 (3H,d) 7.31–7.78 (20H,m)
–1.90(2H,m)
I3
3.51–3.72(1H,t) 2.58–2.72
(2H,d)
7.22–7.58
(15H,m)
7.21–7.95
(30H,m)
7.32–7.90
(30H,m)
7.14–7.32
(30H,m)
7.16–7.45
(30H,m)
7.18–7.50
(30H,m)
7.28–8.04
(30H,m)
6.80–7.05 (5H,m)
7.22–7.58 (20H,m)
0.75–0.82 (6H,d) 7.21–7.95 (12H,m), 2.38 (9H,s)
0.72–0.80 (6H,d) 7.32–7.90 (12H,m)
7.14–7.32 (12H,m)
II1
II2
II3
II4
II5
II6
1.20–1.85
(4H,m)
2.25–2.60
(2H,m)
1.19–1.82
(4H,m)
2.16–2.60
(2H,m)
3.34–3.44
(2H,m)
2.52–2.80
(4H,m)
6.76–7.01 (10H,m)
6.72–7.02 (10H,m)
6.70–7.04 (10H,m)
3.44–3.52
(2H,m)
2.60–2.75
(4H,m)
7.16–7.45 (15H,m)
3.42–3.62
(2H,m)
2.68–2.80
(4H,t)
7.18–7.50 (12H,m), 2.22 (9H,s)
7.28–8.04 (15H,m)
1.41–1.65
(4H,t)
2.18–2.38
(4H,t)
Table 3
The 13C-NMR data (ppm) for compounds I3, II1 and II6
Compd.
GeC
33.1
9.3
CꢀO
CHCꢀO Ph3Ge
ArSb
Others
I3
175.9 38.8
178.5 31.1
180.8 19.6
135.9(i ), 135.2 (o), 128.6(p),
127.9(m)
136.1(i ), 134.8(o), 128.9(p),
128.2(m)
135.1(i ), 134.8(o), 128.7(p),
128.0(m)
142.8(i ), 135.6(o), 130.0(p), 128.8(m) 138.5 (Ph)
II1
II6
138.7(i ), 133.9(o), 130.9(p), 129.1(m)
–
18.3
140.8(p), 137.1(i ), 133.8(o), 130.0(m)
21.4(CH3Ph),
37.0(CH3CH)
Table 4
Fragment ions observed for compounds I3 and II6
I3
II6
M/z
Fragment
Intensity
M/z
Fragment
Intensity
453
429
305
275
227
198
154
121
77
Ph3GeCH(Ph)CH2CO2+
Ph4Sb+
5
35
98
13
20
74
70
6
352
305
301
275
227
198
151
121
74
Ph3Sb+
Ph3Ge+
[Ph3Ge-4H]+
Ph2Sb+
[Ph2Ge-H]+
PhSb+
5
87
100
8
19
69
46
6
Ph3Ge+
Ph2Sb+
[Ph2Ge-H]+
PhSb+
Ph-Ph+
PhGe+
Sb+
Sb+
Ph+
100
7
Ge+
3
74
Ge+
,
equatorial Sb–C distance (mean value 2.102 A). Al-
though the Sb–C distances found here are typical of
Ph4SbBr and Ph4SbOSO2Ph in Table 6. If the normal
,
Sb–O distance is taken as 2.05 A [17], the percentage
,
Sb-aryl bonds, the Sb(1)–O(1) distance is 2.289 A
[longer than typical Sb–O distance (2.05 A), (see Table
6)]. In Ph4SbOC(O)H the Sb–O distance is 2.222 A also
longer than the typical Sb–O value [17]. Similarly, very
long apical Sb–X bonds are also found in Ph4SbCl,
elongation of Sb–O bonds in Ph4SbX, for X=OMe,
OC(O)H, OSO2Ph, Ph3GeCHPhCH2CO2, are 1, 8, 22
and 12%, respectively.
,
,
The crystal structure of compound I3 can be reported
as monomeric. The C–O distances of the carboxyl

238
Y. Ma et al. / Journal of Organometallic Chemistry 620 (2001) 235–242
Fig. 1. The molecular structure of Ph3GeCH(Ph)CH2CO2SbPh4.
,
group are 1.231 and 1.300 A, respectively, which are
The Sb(1)-O(2) and Sb(1)-O(4) distances [2.129(3),
,
typical bond lengths for CꢀO and C–O groups. The
2.146(3) A] are significantly different from the corre-
sponding distances in Ph3Sb(O2CCHCMe2CMe2)2 [both
¸¹¹¹¹º
,
distance between Sb and the carbonyl oxygen is 3.233 A
(cf. Ph4SbOCOH, 3.291 A) which shows a much lower
,
,
2.106(3) A] [18] and Ph3Sb(O2C-2-C4H3S)2 [2.145(4),
,
degree of interaction between the non-bonded oxygen
atom and antimony atom. This is still well within the
sum of the van der Waals’ radii [10]. The smaller Sb···O
interaction leads to a much smaller variation in the
equatorial angles of compound I3 [C(41)–Sb(1)–C(11)
120.54, C(11)–Sb(1)–C(21) 111.79, C(41)–Sb(1)–C(21)
125.08°, in all 357.41°]. The antimony atom is displaced
2.095(4) A] [7]. In this compound there are relatively
strong bonding interactions between Sb(1) and the car-
bonyl oxygens of the carboxylates. The Sb(1)–O(1) and
,
Sb(1)–O(3) distances [2.739(3), 2.647(3) A] are also
different f¸ro¹m¹¹¹thºe corresponding distances in
,
Ph3Sb(O2CCHCMe2CMe2)2 [both 2.800(2) A] and
,
Ph3Sb(O2C-2-C4H3S)2 [2.744(4), 2.949(4) A], which are
,
by 0.1975 A towards C(31) from the plane described by
considerably shorter than the sum of the covalent radii
,
the equatorial carbon atoms C(21), C(41) and C(11). At
the same time, the mean Ceq–Sb–Cap angle is 95.4°
representing a deviation of the equatorial SbC3 frag-
ment from the planar arrangement of a regular trigonal
bipyramid. However, the geometry of compound I3 is
clearly a distorted trigonal bipyramidal with a relatively
small distortion towards tetrahedral.
(3.60A) [19]. This indicates that there are coordination
interactions between the carbonyl oxygens of the two
asymmetrical triphenylgermanylpropionate groups and
the antimony atom. The C(5)–O(1) and C(5)–O(2)
Table 5
Selected bond distances and bond angles of compound I3
,
Bond
Distances (A)
Bond
Angles (°)
2.5.2. Structure of
[Ph3GeCH2CH(CH3)CO2]2Sb(4-ClC6H4)3
Sb(1)–O(1)
Sb(1)–O(2)
Sb(1)–C(41)
Sb(1)–C(11)
Sb(1)–C(21)
Sb(1)–C(31)
Ge(1)–C(71) 1.948(5)
Ge(1)–C(61) 1.951(4)
Ge(1)–C(51) 1.959(5)
Ge(1)–C(3)
O(1)–C(1)
C(1)–O(2)
C(1)–C(2)
C(2)–C(3)
C(3)–C(81)
2.289(3)
3.233(3)
2.121(5)
2.122(5)
2.123(4)
2.170(5)
C(31)–Sb(1)–O(1)
C(41)–Sb(1)–C(11)
C(41)–Sb(1)–C(21)
C(11)–Sb(1)–C(21)
C(41)–Sb(1)–C(31)
C(11)–Sb(1)–C(31)
C(21)–Sb(1)–C(31)
C(41)–Sb(1)–O(1)
C(11)–Sb(1)–O(1)
C(21)–Sb(1)–O(1)
C(71)–Ge(1)–C(61) 110.04(19)
C(71)–Ge(1)–C(51) 108.0(2)
C(61)–Ge(1)–C(51) 109.9(2)
C(71)–Ge(1)–C(3)
C(61)–Ge(1)–C(3)
C(51)–Ge(1)–C(3)
C(1)–O(1)–Sb(1)
O(2)–C(1)–O(1)
177.00(14)
120.54(19)
125.08(19)
111.79(18)
94.07(17)
96.36(18)
95.75(16)
83.78(15)
82.98(16)
87.21(14)
The colorless crystal of [Ph3GeCH2CH(CH3)-
CO2]2Sb(4-ClC6H4)3 was obtained from a CH2Cl2–n-
hexane solution. The molecular structure with the atom
numbering scheme is depicted in Fig. 2. The selected
bond distances and angles are listed in Table 7.
Carboxylates are versatile ligands which can be either
unidentate or bidentate. The molecule consists of a
monomer with a seven-coordinated antimony atom sur-
rounded by four oxygens and three phenyl groups. The
coordination geometry of antimony can be described as
a distorted pentagonal bipyramid with the plane being
defined by four oxygens from two asymmetrically
chelating carboxylate groups and one carbon atom
from one phenyl group, while the other phenyl groups
occupying the axial positions.
2.000(5)
1.300(6)
1.231(6)
1.514(7)
1.508(7)
1.518(6)
111.84(19)
107.86(19)
109.2(2)
118.6(3)
123.7(4)

Y. Ma et al. / Journal of Organometallic Chemistry 620 (2001) 235–242
239
Table 6
Comparision of mean distances in some trigonal bipyramidal antimony compounds
,
d(SbC)ap
d(SbC)eq
d(SbX)ap (A)
C–Sb–X (°)
Ref.
Ph4SbOH
Ph4SbOMe
Ph4SbOC(O)H
Ph4SbOSO2Ph
Ph5Sb
Ph4SbCl
Ph4SbBr
I3
2.128
2.199
2.176
2.131
2.243
2.15
2.131
2.119
2.109
2.108
2.133
2.10
2.048
2.061
2.222
2.506
–
2.74
2.965
2.289
175.4 (O)
178.1 (O)
–
176.0 (O)
178.7 (C)
–
[11]
[12]
[13]
[14]
[15]
[16] a
[17]
2.151
2.170
2.102
2.122
175.5 (Br)
177.0 (O)
This work
a Geometry at Sb intermediate between tetrahedral SbC4 and trigonal bipyramidal SbC4X.
Fig. 2. The molecular structure of [Ph3GeCH2CH(CH3)CO2]2Sb(4-ClC6H4)3.
,
distances [1.208(5), 1.294(6) A] are different from C(3)–
carbonyl oxygen of a neighbouring molecule. The
,
,
O(3) and C(3)–O(4) distances [1.231(5), 1.286(5) A].
They ¸¹ar¹e¹¹aºlso different from those in Ph3Sb-
Cl(2)–O(3) distance is 3.198 A.
,
(O2CCHCMe2CMe2)2 [1.229(6), 1.301(6) A] and
Ph3Sb(O2C-2-C4H3S)2 [1.226(6), 1.305(6), 1.215(6),
Table 7
,
1.309(6) A]. The O(3)–Sb(1)–O(1), O(3)–Sb(1)–O(4)
Selected bond distances and bond angles of compound II2
and O(1)–Sb(1)–O(2) angles are 79.3, 53.0 and 51.6°,
respectively. The plane angles are 360.3° in all. The
C(9)–Sb(1)–C(21) angle, which is affected by adjacent
O(1) and O(3), is increased to 149.86°, while the C(15)–
Sb(1)–C(21) and C(15)–Sb(1)–C(9) angles are de-
creased to 104.33(19)° and 105.81(18)°, respectively.
The corresponding angles in Ph3Sb(O2C-2-C4H3S)2 are
145.9(¸2)¹, ¹1¹0¹4º.4(2) and 109.5(2)°, which in Ph3Sb-
(O2CCHCMe2CMe2)2 are 150.0(3), 105.1(2) and
105.1(2)°. These differences can be attributed to the –I
effect of Cl of the aryl groups and the steric effect of
the two bulkyl triphenylgermanylpropionate groups in
the molecule. The –I effect of Cl enhances the Lewis
acidity of Sb and leads to the stronger Sb···OꢀC coordi-
nation [20]. The atoms Sb(1), O(1), O(2), O(3), O(4)
,
Bond
Distances (A) Bond
Angles (°)
Sb(1)–O(2)
Sb(1)–O(4)
Sb(1)–O(1)
Sb(1)–O(3)
Ge(1)–C(33)
Ge(1)–C(1)
Ge(2)–C(57)
Ge(2)–C(7)
O(1)–C(5)
O(3)–C(3)
O(2)–C(5)
O(4)–C(3)
Cl(2)–O(3)
2.129(3)
2.146(3)
2.739(3)
2.647(3)
1.951(5)
1.965(5)
1.947(6)
1.970(5)
1.208(5)
1.231(5)
1.294(6)
1.286(5)
3.198
C(9)–Sb(1)–C(21)
C(21)–Sb(1)–C(15) 104.33(19)
149.86(19)
C(9)–Sb(1)–C(15)
O(2)–Sb(1)–O(4)
C(9)–Sb(1)–O(2)
C(9)–Sb(1)–O(4)
C(21)–Sb(1)–O(4)
105.81(18)
176.42(13)
90.45(15)
90.78(15)
89.41(15)
C(33)–Ge(1)–C(39) 109.5(2)
C(51)–Ge(2)–C(7) 109.7(3)
O(3)–C(3)–O(4)
O(1)–C(5)–O(2)
C(15)–Sb(1)–O(2)
C(21)–Sb(1)–O(2)
C(15)–Sb(1)–O(4)
O(3)–Sb(1)–O(1)
O(3)–Sb(1)–O(4)
O(1)–Sb(1)–O(2)
120.5(4)
122.2(4)
87.92(15)
91.21(15)
88.51(15)
79.3(4)
,
and C(15) are coplanar within 0.0703 A.
53.0(4)
51.6(4)
In the unit cell there is a surprising weak intermolec-
ular interaction between the Cl atom of aryl group and

240
Y. Ma et al. / Journal of Organometallic Chemistry 620 (2001) 235–242
Table 8
Yields and elemental analyses of the compounds
Compound
Yield (%)
M.p. (°C)
Elemental analysis: found (calcd.) (%)
Formula for calc.
C
H
I1
I2
I3
II1
II2
II3
II4
II5
II6
61.8
51.3
86.3
85.4
91.6
43.1
73.1
64.7
62.6
160–162
173–175
168–170
208–210
160–161
190–192
209–211
179–181
208–209
66.99 (67.05)
67.16 (67.36)
68.94 (69.43)
66.57 (66.44)
60.06 (60.23)
63.50 (63.56)
68.65 (68.79)
69.25 (69.33)
64.74 (65.22)
4.92 (4.88)
5.01 (5.04)
5.02 (4.91)
5.11 (5.40)
4.13 (4.40)
4.45 (4.30)
5.04 (4.89)
5.05 (5.20)
4.90 (4.83)
C45H39GeO2Sb
C46H41GeO2Sb
C51H43GeO2Sb
C65H63Ge2O4Sb
C62H54Cl3Ge2O4Sb
C72H58Cl3Ge2O4Sb
C72H61Ge2O4Sb
C75H67Ge2O4Sb
C60H53Ge2O4Sb
Table 9
Crystallographic data for compound II2 and I3
3. Experimental
Elemental analyses were determined on a Yanaco
CHN Corder MT-3 elemental analyzer. IR spectra were
recorded on a Bruker Equinox 55 spectrometer in KBr
Compound
II2
I3
Formula
Temperature (K)
Wavelength (A)
C62H54Cl3Ge2O4Sb
298
0.71073
C51H43GeO2Sb
298
0.71073
1
discs. H-NMR and 13C-NMR spectra were measured
,
on a Bruker AC-200 spectrometer or JEOL-FX-90Q
spectrometer in CDCl3 solution with TMS as internal
standard. Mass spectra were recorded on a HP-5988A
mass spectrometer (EI) at 70 eV, the temperature of
ionization was 200°C. All the reactions involving metal
halides were carried out under anhydrous and oxygen-
free argon atmosphere. Solvents were purified, dried,
and stored by literature methods.
Crystal system
Space group
Unit cell dimensions
Monoclinic
P2(1)/n
Monoclinic
C2/c
,
a (A)
13.2650
23.5968
18.5131
90
106.1420
90
5566.4
4
1.474
1.745
16.2787
22.946
26.013
90
107.640
90
9259.9
8
1.353
1.276
,
b (A)
,
c (A)
h (°)
i (°)
k (°)
Volume (A )
Z
3
,
Density (Mg mm−3
Absorption
coefficient
)
3.1. Reagents
The substituted b-triphenylgermanylpropionic acids
were synthesized via the following reaction [25,26].
R3SbBr2 was prepared by the method reported by W.J.
Lice and co-workers [27]. R3Sb was converted into the
corresponding dibromide by direct bromination, and
the solid product was recrystallized from toluene–
petroleum ether mixture. To prepare Ph4SbBr an adap-
tation of the method of W.E. Mcewen and co-workers
[4] was used. A suspension of 25.4 g (0.06 mol) of
triphenylantimony dichloride in a mixture of ether (160
ml) and toluene (80 ml) was added slowly with stirring
to a solution of phenylmagnesium bromide (0.18 mol)
in 250ml of ether. The mixture was stirred occasionally,
and allowed to remain at room temperature (r.t.) for 6
days. A large amount of product had precipitated
during this period. To the stirred mixture was added
slowly 20 g ice and 26 ml of 40% hydrobromic acid,
and the mixture were stirred overnight. After filtration
and recrystallization of the precipitate from water–eth-
anol (3:2), the tetraphenylstibonium bromide weighed
16.6 g (54.4%) and had a m.p. 212–214°C (lit. 210–
215°C).
(mm−1
F(000)
)
2492
0.20×0.25×0.30
1.69–25.03
3348
0.30×0.25×0.20
1.58–25.03
Crystal size (mm)
q Range for data
collection (°)
Limiting indices
−155h510,
−275k528,
−205l522
−195h515,
−275k527,
−305l530
19 138
Reflection collected 22 885
Independent
reflections
Completeness to
q=25.03°
Absorption
correction
9785 (Rint=0.0477) 8191 (Rint=0.0416)
99.5%
None
100.0%
SADABS
Refinement method Full-matrix
least-squares on F2
0.972
Full-matrix
least-squares on F2
1.063
Goodness-of-fit on
F2
Final R indices
[I\|(I)]
R indices (all data) R1=0.0860,
wR2=0.1053
R1=0.0412,
wR2=0.0884
R1=0.0456,
wR2=0.1232
R1=0.0599,
wR2=0.1313
1.150 and −0.771
Large difference
peak and hole
1.077 and −0.890
(e A−3
)

Y. Ma et al. / Journal of Organometallic Chemistry 620 (2001) 235–242
241
Table 10
Antitumor activity of the selected compounds in vitro
Compound
X9S.D. a, inhibition ratio (%) (10 mM)
HL-60 cells
EJ cells
Skov3 cells
Hela cells
BGC-823 cells
I2
I3
1.52290.179, 31.7
2.2469.404, −24.8
0.7199.0.025, 67.7
0.29590.041, 46.7
1.38790.286, 30.0
1.94490.068, 12.71
0.9
–
0.6290.037, 14.5
0.67490.027, 10.9
0.590.013, 30.8
0.55390.025, 26.9
0.60690.091, 19.9
–
2.00690.091, 13.6
1.59190.439, 27.9
2.08390.241, 9.83
1.22790.017, 44.4
1.16590.268, 47.2
1.84290.227, 16.54
0.3
0.70590.026, 15.1
0.66290.017, 22.5
0.5490.078, 37.2
0.83390.048, 8.2
2.12990.076, 1.0
0.80390.071, 6.52
–
1.07490.065, 8.5
0.2390.034, 80.5
091190.32, 22.4
–
1.08890.026, 7.33
7.9
II2
II4
II5
II6
a b
5.8
a X9S.D., the observed mean values and the standard devation.
b Ph3GeCH2CHCH3CO2H.
GeO2+HCl+NaH2PO2
tain activities against cancer cells in vitro. The com-
pounds including organoantimony moiety have
relatively higher antitumor activities than triphenylger-
manylpropionic acid. The antitumor data indicate that
the antitumor activities are affected by the nature of the
aryl and the triphenylgermanylpropionic acids, for ex-
ample, when R3 is 4-ClC6H4 compound II2 has rela-
tively higher antitumor activity.
1
2
CHR =CR CO H
“HGeCl3 ꢁꢁꢁꢁꢁꢁꢁꢁꢁꢁꢁ2ꢁꢂ Cl3GeCHR1CHR2CO2H
4PhMgBr
ꢁꢁꢁꢁꢁꢁꢁꢁꢂ Ph3GeCHR1CHR2CO2H
+
H
/H O
2
3.2. Synthesis of the title compounds
The title compounds were synthesized by a more
convenient method. Typically, to b-triphenylgermanyl-
propionic acid (1 mmol) and triethylamine (0.8 ml) in
toluene (40 ml) was added 0.5 mmol of R3SbBr2 (or 1
mmol of Ph4SbBr). The reaction mixture was stirred at
r.t. for 6–8 h and filtered. The filtrate was evaporated
in vacuo. The obtained solid was recrystallized from
CH2Cl2–petroleum ether. The yields, melting points
and elemental analysis of the prepared compounds are
given in Table 8.
5. Supplementary material
Crystallographic data for the structures reported in
this paper have been deposited with the Cambridge
Crystallographic Data Centre, CCDC no. 146615 for
compound I3 and CCDC no. 146616 for compound II2.
Copies of this information may be obtained free of
charge from the Director, CCDC, 12 Union Road,
Cambridge, CB2 1EZ, UK (fax: +44-1223-336033;
e-mail: deposit@ccdc.cam.ac.uk or http://www.ccdc.
cam.ac.uk).
3.3. Crystal structure determination
Diffraction measurements of compounds I3 and II2
were carried out at 298 K on a Bruker Smart 1000
diffractometer (graphite-monochromatized Mo–Ka ra-
Acknowledgements
,
diation, u=0.71073 A). The crystal class, orientation
matrix and accurate unit-cell parameters were deter-
mined by standard procedures. The intensities were
corrected for absorption using SADABS program. The
structure was solved by heavy atom method and refined
by a full-matrix least square procedure based on F2.
Non-hydrogen atoms were refined with anisotropic
thermal parameters. Crystal data are summarised in
Table 9.
We thank that Professor Linhong Weng and assistant
Professor Xuebin Leng for support of the crystallo-
graphic study. We are also grateful to Professor
Ruiqing Wang and Professor Kui Wang of National
Research Laboratories of Natural and Biomimetic
Drugs of Beijing Medical University for testing antitu-
mor activity.
References
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242
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