The title cyclopropane derivative, C18H12O3S3, was synthesized

and its structure investigated by single-crystal

X-ray diffraction and spectroscopic methods. This structure

analysis addresses the problem of spontaneously resolved

helical stereoisomerism. The temperature-dependent

1H NMR spectrum shows a relevant barrier to rotation

about the CO-thiophene bonds, with ∆G423 -~

89 (21) kJ mo1-1

Saba, Antonio

English

UnissResearch

VIOSSAT et al. 271 
Collection des donn~es 
Diffractom6tre 4 cercles 
Syntex Nicolet P21 
Balayage 0-20 
Correction d'absorption: 
n6ant 
2488 r/~tlexions mesur6es 
2488 r6flexions 
ind6pendantes 
1155 rbflexions observ6es 
[I > 2o'(/)1 
Affinement 
Affinement bas+ sur les F 
R -- 0,056 
wR = 0,042 
S = 2,02 
1155 r6flexions 
175 param6tres 
Les param6tres x, y, z des 
atomes d'hydrog6ne af- 
fin~s 
w = lfir2(F) 
0max = 21 o 
h = -12  ~ 12 
k = 0 ---~ 9 
l =0-- -*24 
3 r6flexions de r6f6rence 
mesurees toutes les 50 
r6flexions 
variation d'intensit& 
< 0,1% 
(A/if)max = 0,48 
Apmax = 0,26 e ,~-3 
mpmin = -0,25 e ,~-3 
Correction d'extinction: 
n6ant 
Facteurs de diffusion de 
International Tables for 
X-ray Crystallography 
(1974, Tome IV) 
Tableau 1. Coordonnbes atomiques et facteurs d'agitation 
thermique isotropes ~quivalents (~2) 
Beq -- (4/3)Ei~,j~3ijai.aj. 
x y z Beq 
S 0,4375 (1) 0,1101 (2) 0,65617 (7) 4,02 
N(1) 0,3873 (4) -0,1499 (6) 0,5430 (2) 2,94 
C(2) 0,3521 (5) 0,0305 (7) 0,5742 (2) 2,83 
N(3) 0,2392 (4) 0,1369 (6) 0,5327 (2) 3,04 
C(4) 0,1582 (5) 0,0769 (8) 0,4634 (2) 3,04 
C(5) 0,1466 (5) -0,1958 (8) 0,3603 (2) 3,01 
C(6) 0,2029 (5) -0,3751 (8) 0,3395 (3) 3,28 
C(7) 0,3149 (5) -0,4873 (8) 0,3866 (3) 3,22 
0(8) 0,3663 (3) -0,3974 (5) 0,4568 (2) 3,17 
C(9) 0,3159 (5) -0,2171 (7) 0,4758 (3) 2,67 
C(10) 0,2046 (4) -0,1136 (8) 0,4326 (2) 2,75 
0(40) 0,0575 (4) 0,1860 (5) 0,4346 (2) 4,66 
C(50) 0,0294 (6) - 0,086 (1) 0,3073 (3) 4,45 
0(70) 0,3706 (4) -0,6472 (5) 0,3743 (2) 4,12 
C(100) -0,1946 (7) 0,432 (1) 0,3389 (4) 5,25 
O(110) -0,1494 (4) 0,4929 (6) 0,4146 (2) 4,47 
Tableau 2. Param&res gbombtriques (A, o) 
s-c(2) 1,639 (5) c(5)-c(10) 1,429 (6) 
N(I)--C(2) 1,367 (5) C(5)--C(50) 1,498 (7) 
N(1)--C(9) 1,352 (5) C(6)--C(7) 1,425 (6) 
N(3)--C(2) 1,364 (5) C(7)--O(8) 1,404 (5) 
N(3)--C(4) 1,401 (5) C(7)--O(70) 1,198 (5) 
C(4)--O(40) 1,214 (5) O(8)--C(9) 1,330 (5) 
C(4)--C(10) 1,452 (6) C(9)--C(10) 1,359 (5) 
C(5)--C(6) 1,355 (6) C(100)--O(110) 1,414 (7) 
C(2)--N(1)--C(9) 122,4 (4) C(5)--C(6)--C(7) 123,4 (5) 
N(I)--C(2)--S 122,2 (3) O(70)--C(7)--C(6) 128,7 (5) 
N(3)--C(2)--S 122,8 (4) O(70)--C(7)--O(8) 116,0 (4) 
N(1)--C(2)--N(3) 114,9 (4) C(6)--C(7)--O(8) 115,2 (4) 
C(2)--N(3)--C(4) 126,3 (4) C(9)--O(8)--C(7) 121,4 (4) 
O(40)--C(4)--N(3) 118,2 (5) O(8)--C(9)--N(I) 112,3 (4) 
O(40)--C(4)--C(10) 126,1 (4) O(8)--C(9)--C(10) 123,6 (4) 
N(3)--C(4)--C(10) 115,7 (4) N(I)--C(9)--C(10) 124,1 (5) 
C(6)--C(5)--C(10) 118,2 (4) C(9)--C(10)--C(5) 118,0 (5) 
C(6)--C(5)--C(50) 120,2 (5) C(9)--C(10)--C(4) 116,5 (4) 
C(10)--C(5)--C(50) 121,6 (5) C(5)--C(10)--C(4) 125,5 (4) 
Enregistrement des intensit6s: toutes les intensit6s on 6t6 cor- 
rig6es des effets de Lorentz et de polarisation. La structure a
© 1994 International Union of Crystallography 
Printed in Great Britain - all rights reserved 
6t6 r6solue ~i l'aide des m6thodes directes (MULTAN88; De- 
baerdemaeker t al., 1988). L'affinement des param6tres x, y, 
z, B pour les atomes non-hydrog6nes t x, y, z pour les atomes 
d'hydrog6ne, a &6 effectu6 h l'aide du programme ORXFLS 
(Busing, 1971). Les dessins de la structure ont 6t6 obtenus/t 
l'aide du programme ORTEPII (Johnson, 1976). Les angles 
di6dres ont 6t6 calcul6s ~ l'aide du programme BEST PLANES 
(Ito & Sugawara, 1983). 
Les listes des facteurs de structure, des facteurs d'agitation thermique 
anisotrope, des coordonn6es des atomes d'hydrog6ne, des distances et 
angles des atomes d'hydrog6ne, des plans moyens et des angles de tor- 
sion ont 6t6 d6pos6es au d6p6t d'archives de la British Library Document 
Supply Centre (Supplementary Publication No. SUP 71241:12 pp.). On 
peut en obtenir des copies en s'adressant a: The Technical Editor, Inter- 
national Union of Crystallography, 5 Abbey Square, Chester CH 1 2HU, 
Angleterre. [R6f6rence de CIF: PA 1040] 
R6f6rences 
Busing, W. R. (1971). Acta Cryst. A27, 683-684. 
Debaerdemaeker, T., Germain, G., Main, P., Refaat, L. S., Tate, 
C. & Woolfson, M. M. (1988). MULTAN88. A System of 
Computer Programs for the Automatic Solution of Crystal Struc- 
tures from X-ray Diffraction Data. Univ. de York, Angleterre, t 
Louvain, Belgique. 
lto, T. & Sugawara, Y. (1983). Best Plane Program, 36me 
R6vision. The Institute of Physical and Chemical Research, 
Wako-Shi, Saitama 351, Japon. 
Johnson, C. K. (1976). ORTEPII. Report ORNL-5138. Oak 
Ridge National Laboratory, Tennessee, EU. 
Ridi, M. (1950). Gazz. Chim. Ital. 80, 121-128. 
Tomas, A., Nguyen-Huy, D., Viossat, B., Esanu, A. & Rolland, 
A. (1993). Acta Cryst. C49 626-628. 
Acta Cryst. (1994). C50, 271-274 
Synthesis and Structure of trans-l,2,3- 
Tris(3-thenoyl)cyclopropane 
ANTOMO SABA 
Dipartimento di Chimica, Universit& di Sassari, 
Via Henna 2, 1-7100 Sassari, Italy 
(Received 12 May 1993; accepted 18 August 1993) 
Abstract 
The title cyclopropane derivative, C18H120383, was syn- 
thesized and its structure investigated by single-crystal 
X-ray diffraction and spectroscopic methods.  This struc- 
ture analysis addresses the problem of spontaneously re- 
solved helical stereoisomerism. The temperature-depend-  
ent 1H NMR spectrum shows a relevant barrier to ro- 
tation about the CO- th iophene bonds, with AG423 -~ 
89 (21) kJ mo1-1. 
Acta Crystallographica Section C 
ISSN0108-2701 ©1994 
272 C18H1203S3 
Comment 
Recently, aconvenient synthesis of 1,2,3-tris(aroyl)cyclo- 
propanes (1) by the one-step cyclotrimerization of 2- 
bromoacetylarenes and heteroarenes was reported (Saba, 
1990). The uniquivocal steric course of the reaction, with 
regard to the 1,2-trans ubstitution i  the cyclopropane 
ring of (1), has been derived by crystal structure analysis 
and confirmed by NMR analysis. 
COAr 
1 
ArCOCH2Br ~ ArCO A COAr 
(1) 
We report herein the synthesis and structure deter- 
mination of trans-l,2,3-tris(3-thenoyl)cyclopropane (2), 
which presents an unusual case of spontaneously resolved 
helical stereoisomerism. The configuration of one of the 
enantiomers i  resolved by the present structure analysis. 
Moreover, the temperature-dependent 1H NMR spectra in 
MezSO confirm the hindered rotation around the bonds 
between the carbonyl and thienyl groups at room temper- 
ature. 
s 
s 
o,, 
(2) 
Fig. 1 shows a molecule of the title compound and its 
numbering scheme. The assumed enantiomer is that with 
the lowest R values, R -- 0.054 and wR -- 0.067, while 
the opposite nantiomer gives R -- 0.058 and wR -- 0.072. 
The orientations of the carbonyl groups with respect o 
cyclopropane are defined by the torsion angles O1-- 
C5--C6--C8 19(1), O2--C9--C7--C6 -17(1)  and 
O3--C14--C8--C7 -31 (1)°; the torsion angles about 
the CO-thiophene bonds are O1--C5--C4--C3 
172.4(9), O2--C9--C10--C13 -162.0(9) and 03- -  
C14--C15--C16 -179.5(7) ° . The S1, $2 and $3 
heterocyclic rings are inclined at dihedral angles of 
80.7 (5), 61.9 (6) and 54.8 (7) °, respectively, to the C6-- 
C7--C8 plane. The dihedral angles between the carbonyl 
planes and the linked thiophene rings are 6.1 (3), 16.8 (3) 
and 1.3 (4) ° for the rings containing S1, $2 and $3, re- 
spectively. 
Fig. 2 shows the XH NMR (300 MHz) spectra of (2) in 
deuterated Me2SO at various temperatures. As the sam- 
ple was warmed, an upfield shift of two extra deshielded 
signals, due to single protons near sulfur in the thio- 
phene rings, was observed. The signals exhibited by the 
neighbouring protons at 7.70 (dd), 7.57 (m) and 7.60 
(m), 7.47 (dd) p.p.m, collapse to two singlets at 7.64 and 
S~~ )Cl7 . 
C18 ~)C 18 
02 C3 
CIO~cIS 
C12 ~ $2 
Fig. 1. ORTEP (Johnson, 1965) view of the molecule in its assumed 
absolute configuration showing the atomic numbering scheme. Ellip- 
soids are at the 50% probability level. 
9 8.6 8.2 7.8 7.4 7.0 
Fig. 2. Temperature-dependent I H (300 MHz) NMR spectrum of the 
aromatic protons. 
ANTONIO SABA 273 
7.52 p.p.m., respectively, at 528 K through a coalescence 
temperature of ca 423 K. The free-energy value at this 
temperature (AG423) was calculated (Abraham, Fischer & 
Loftus, 1988) to be ca 88.8 (21.2) kJ mo1-1 . With respect 
to the cyclopropane protons, no temperature dependence 
of the shift in signals was observed. 
Exper imenta l  
Crystal data 
C1sH1203S3 Cu Kc~ radiat ion 
Mr = 372.47 A = 1.5418 ,~, 
Orthorhombic Cell parameters from 10 
Pna2 ~ reflections 
a = 14.645 (2) A 0 = 23.2-26.5 ° 
b = 20.891 (5) ,~ /z = 4.221 mm -I 
c = 5.404 (2) A T = 296 K 
V = 1653.3 (8) A 3 Needles 
Z = 4 0.30 x 0.05 × 0.02 mm 
Dx = 1.496 Mg m -3 Colourless 
Data collection 
Rigaku AFC-5R diffractome- 
ter 
w-20 scans 
Absorption correction: 
empirical (azimuthal scan) 
Tmin -- 0.84, Tmax = 1.00 
2852 measured reflections 
1490 independent reflections 
1032 observed reflections 
[I > 3o~(/)l 
Rint = 0.051 
0max = 60.1 o 
h = -16  ~ 16 
k=0~23 
1 =046 
3 standard ref lect ions 
mon i to red  every  150 
ref lect ions 
intensity variat ion: none 
Refinement 
Refinement on F 
R -- 0.054 
wR -- 0.067 
S = 1.96 
1032 reflections 
190 parameters 
All H-atom parameters 
refined 
w = 4FZIo'E(Fo 2)
mpmax = 0.41 e A -3 
Apmin = -0 .29  e A -3 
Atomic scattering factors 
from International Tables 
for X-ray Crystallogra- 
phy [1974, Vol. IV, Tables 
2.2A and 2.3.1 (C, O, S) 
and 2.2C (H)] 
Table 1. Fractional atomic coordinates and equivalent 
isotropic displacement parameters (,~2) 
Ueq = (1/3)Ei~jUija~ a~ ai.aj. 
x y z Ueq 
S1 0.5514 (2) 0.5878 (1) 0.7909 0.081 (1) 
$2 0.1723 (2) 0.2283 (1) 1.1851 (9) 0.082 (1) 
S3t 0.0616 (4) 0.7070 (2) 0.851 (1) 0.051 (2) 
$23t -0.0010 (10) 0.7044 (3) 1.162 (2) 0.061 (2) 
O1 0.2744 (4) 0.5592 (3) 1.274 (1) 0.059 (2) 
02 0.2486 (5) 0.3956 (3) 0.595 (1) 0.055 (3) 
03 0.0720 (4) 0.5013 (3) 1.286 (1) 0.057 (3) 
CI 0.4521 (6) 0.6108 (4) 1.157 (2) 0.057 (3) 
C2 0.5363 (6) 0.6263 (4) 1.066 (2) 0.040 (3) 
C3 0.4449 (6) 0.5539 (4) 0.796 (2) 0.041 (3) 
C4 0.3976 (5) 0.5700 (3) 1.003 (2) 0.039 (2) 
C5 0.3066 (6) 0.5469 (4) 1.073 (2) 0.034 (2) 
C6 0.2564 (5) 0.5072 (3) 0.890 (2) 0.040 (3) 
C7 0.2176 (5) 0.4445 (3) 0.983 (2) 0.047 (3) 
C8 0.1559 (5) 0.4971 (3) 0.906 (2) 0.045 (3) 
C9 0.2298 (5) 0.3884 (4) 0.814 (2) 0.058 (3) 
Cl0 0.2208 (6) 0.3225 (3) 0.921 (2) 0.069 (4) 
C ll 0.2499 (5) 0.2680 (4) 0.794 (2) 0.056 (3) 
C12 0.2303 (7) 0.2126 (4) 0.914 (2) 0.044 (3) 
C13 0.1780 (6) 0.3084 (4) 1.138 (2) 0.071 (6) 
C14 0.0987 (5) 0.5301 (4) 1.102 (2) 0.039 (5) 
C15 0.0727 (4) 0.5972 (2) 1.055 (1) 0.045 (2) 
C16 0.1017 (5) 0.6292 (2) 0.850 (1) 0.044 
C17 0.0041 (8) 0.6990 (3) 1.129 (2) 0.026 (4) 
C18 0.0122 (8) 0.6370 (3) 1.236 (2) 0.071 (6) 
C25 0.0727 0.5972 1.0552 0.045 
C26 0.0160 (10) 0.6240 (3) 1.225 (2) 0.022 (6) 
c27 0.0690 (10) 0.7045 (3) 0.905 (3) 0.040 (10) 
c28 0.1090 (10) 0.6437 (4) 0.852 (3) 0.070 (10) 
t $3 (C15-C18) and $23 
tions of the ring (see text). 
(C25-C28) are two alternative conforma- 
Table 2. Selected geometric parameters (A, o) 
S1--C2 1.70 (1) C10--C13 
S1--C3 1.713 (9) Cll--C12 
$2--C12 1.72 (1) C14--C15 
O1--C5 1.21 (1) C14--C25 
O2--C9 1.22 (1) C15--C16 
O3--C14 1.23 (1) C15--C18 
C1--C2 1.37 (1) C15--C26 
CI--C4 1.43 (1) C15--C28 
C3--C4 1.36 (1) C16--C25 
C4--C5 1.47 (1) C16--C27 
C5--C6 1.49 (1) C17--C18 
C6--C7 1.51 (1) C17--C26 
C6--C8 1.49 (1) C17--C27 
C7--C8 1.48 (1) C18--C25 
C7--C9 1.50 (1) C25--C26 
C8--C14 1.52 (I) C25--C28 
C9--C10 1.50 (1) C27--C28 
CI0--Cl l  1.40 (1) 
C2--S1--C3 93.6 (4) C16--C15--C26 
C12--$2--C13 92.1 (4) C16--C15--C18 
C2--C1--C4 115.7 (8) C15--C16--C28 
S1--C2--C1 108.6 (7) C15--C16--C27 
SI--C3--C4 112.0 (6) C15--C16--C25 
CI--C4--C3 110.0 (8) C27--C16--C28 
C3--C4--C5 126.5 (8) C25--C16--C28 
CI--C4--C5 123.5 (7) C25--C16--C27 
O 1 --C5--C4 121.0 (8) C26--C 17--C27 
C4--C5--C6 117.5 (7) C18--C17--C27 
OI--C5--C6 121.5 (9) C18--C17--C26 
C5--C6--C8 122.0 (7) C15--C18--C17 
C5--C6--C7 116.6 (6) C17--C18--C26 
C7--C6--C8 59.2 (5) C17--C18--C25 
C6--C7--C9 115.5 (6) C15--C18--C26 
C6--C7--C8 59.6 (4) C 15--C 18--C25 
C8--C7--C9 118.8 (6) C25--C 18--C26 
C6--C8--C7 61.2 (5) C16--C25--C18 
C7--C8--C14 118.5 (6) C15--C25--C18 
C6--C8--C14 121.5 (7) C14--C25--C18 
O2--C9--C7 121.4 (9) C14--C25--C16 
C7--C9--C10 118.3 (6) C14--C25--C15 
O2--C9--C10 120.4 (8) C18--C25--C28 
C9--C10--C13 124.8 (8) C18--C25--C26 
C9--C10--CI 1 122.2 (6) C16--C25--C28 
CII--CI0--CI3 112.8 (9) C16--C25--C26 
C10--CI1--CI2 113.3 (7) C15--C25--C28 
$2--C12--C11 110.3 (8) C15--C25--C26 
$2--C13--C10 111.4 (6) C14--C25--C28 
O3--C14--C8 121.3 (8) C14--C25--C26 
C8--C14--C25 117.1 (6) C26--C25--C28 
C8--C14--C15 117.0 (6) C18--C26--C25 
O3--C14--C25 121.6 (7) C17--C26--C25 
O3--C14--C15 121.6 (8) C17--C26--C18 
C15--C14--C25 0.0 (2) C15--C26--C25 
C14--C15--C28 128.7 (6) C15--C26--C18 
C14--C15--C26 115.7 (5) C15--C26--C17 
C14--C15--C25 80.1 (4) C16--C27--C17 
1.36(1) 
1.36(1) 
1.47 (0) 
1.474 (8) 
1.362 (8) 
1.56(1) 
1.36(1) 
1.56(1) 
1.363 (5) 
1.671 (9) 
1.42 (1) 
1.66 (1) 
1.54(1) 
1.56(1) 
1.36(1) 
1.56 (1) 
1.43 (1) 
122.6 (7) 
115.2 (6) 
123 (2) 
103.2 (4) 
o.o (2) 
37 (2) 
123 (2) 
103.2 (4) 
104.5 (6) 
109.6 (7) 
5.8 (3) 
106.1 (5) 
143 (2) 
I06.1 (5) 
41 (2) 
o.o (2) 
41 (2) 
115.2 (4) 
129 (8) 
123.1 (4) 
121.7 (4) 
99.9 (4) 
107.6 (6) 
7.9 (5) 
10.0 (5) 
122.6 (5) 
45 (4) 
133 (3) 
128.7 (5) 
115.7 (4) 
115.3 (7) 
131 (2) 
104.0 (5) 
31 (2) 
o.o (2) 
131 (2) 
104.0 (5) 
104.2 (6) 
274 C18H120383 
C14--C15--C18 123.1 (5) C17--C27--C28 110.1 (9) 
C14--C15--C16 121.8 (5) C16--C27--C28 7.8 (4) 
C26--C15--C28 115.3 (8) C25--C28--C27 105.8 (6) 
C25--C15--C28 135 (4) C16--C28--C27 135 (2) 
C25--C15~C26 47 (3) C16--C28--C25 47 (2) 
C18--C15--C28 107.6 (7) C15--C28--C27 105.9 (6) 
C18--C15--C26 7.9 (5) C15--C28--C25 0.0 (2) 
C18--C15~C25 51 (7) C15--C28--C16 47 (2) 
C16--C15--C28 10.0 (5) 
All reagents and solvents were of reagent grade and used without 
further purification. (2) was obtained as colourless needles, m.p. 
469-470 K (crystallized from isobutyl methyl ketone) in 91% 
yield by treatment of 10 mmol of 3-(bromoacetyl)thiophene 
(McDowell & Greenwood, 1965) with 6 mmol of K2CO3 in 
DMF at room temperature for 6 h, water quenching, neutral- 
ization with 10% HC1 and filtration. Analysis: calculated for 
C18H1203S3 C 58.03, H 3.22, S 25.82%; found C 58.32, H 3.11, 
S 25.56%. 
1H (300 MHz) and 13C (75 MHz) NMR spectra of (2) were 
recorded on a Varian VXR-300 spectrometer, with CDC13 or 
Me2SO as solvents and TMS (tetramethylsilane) as the inter- 
nal standard. 1H NMR (CDC13, 300 MHz) 6:8.42 (1H, da~ J = 
1.2, 3 Hz), 8.14 (2H, dd, J = 1.2, 3 Hz), 7.68 (1H, dd, J = 1.2, 
5.1 Hz), 7.54 (2H, dd, J = 1.2, 5.1 Hz), 7.38 (1H, dd, J = 1.2, 
5.1 Hz), 7.28 (2H, dd, J = 3, 5.1 Hz), 4.04 (1H, t, J -- 5.7 Hz), 
3.58 (2H, a~ J -- 5.7 Hz). 13C NMR (CDC13, 75 MHz): 189.7, 
186.7, 141.8, 141.6, 134.2, 132.9, 126.9, 126.8, 126.7, 126.6, 
36.6, 30.9. 
Intensity data were corrected for Lorentz and polarization 
effects. H atoms were included in the structure-factor cal- 
culations in idealized positions (C--H = 0.95 A), and were 
assigned isotropic displacement parameters 20% greater than the 
U~q value of the atom to which they were bonded. Because the 
S3-thiophene ring in the molecule is disordered, the C4S five- 
membered rigid-body rings were generated based on the average 
geometry of the other two thiophene rings, which were located 
from difference Fourier maps and refined by full-matrix least 
squares. The rigid-body rings were refined isotropically with 
populations of 0.65 (1) for the ring containing $3 and 0.35 (1) 
for the ring containing $23. H atoms were not included for the 
rigid'body rings owing to problems with disorder in the refine- 
ments. Program(s) used to solve structure: MITHRIL (Gilmore, 
1984). Program(s) used to refine structure: TEXSAN (Molecu- 
lar Structure Corporation, 1985). Molecular graphics: ORTEP 
(Johnson, 1965). Anomalous-scattering coefficients were taken 
from International Tables for X-ray Crystallography (1974, Vol. 
IV). 
Molecular Structure Corporation (1985). TEXSAN. TEXRAY Structure 
Analysis Package. MSC, 3200 Research Forest Drive, The Wood- 
lands, TX 77381, USA. 
Saba, A. (1990). J. Chem. Res. (S), pp. 288-289. 
Acta Cryst. (1994). C50, 274-276 
Structure of a Model for the Aranorosin 
Nucleus 
R. CURTIS HALTIWANGER AND DRAKE S. EGGLF_SIDN 
SmithKline Beecham Pharmaceuticals, Box 1539 
UW2950, King of Prussia, PA 19406, USA 
ANDREW McKILLOP, R. J. K. TAYLOR AND R. J. WATSON 
School of Chemical Sciences, University of East 
Anglia, Norwich NR4 7T J, England 
NORMAN LEWIS 
SmithKline Beecham Pharmaceuticals, Leigh, 
Tonbridge, Kent TNll 9AN, England 
(Received 5May 1993; accepted 31 August 1993) 
Abstract 
The structure of a synthetic model system, 2-hydroxy- 
6,7 ;9,10-cis,cis-diepoxy- 1-oxaspiro [4.5] decan- 8-one, 
C9H1005, for the spirocyclic headgroup of the natural 
product aranorosin has been determined and shown to 
possess the natural product stereochemistry. Two crys- 
tallographlcally independent molecules cocrystallize in a 
centrosymmetric space group. The syn arrangement of the 
diepoxides and the lactol O atom about he cyclohexanone 
ring has been confirmed in both molecules. The cyclohex- 
anone ring adopts a boat conformation with the carbonyl 
O atom anti to the lactol O atom. 
Lists of structure factors, anisotropic displacement parameters, H-atom 
coordinates and complete geometry have been deposited with the British 
Library Document Supply Centre as Supplementary Publication No. 
SUP 71592 (17 pp.). Copies may be obtained through The Technical 
Editor, International Union of Crystallography, 5 Abbey Square, Chester 
CH1 2HU, England. [CIF reference: LI1065] 
References 
Abraham, R. J., Fischer, J. & Loftus, P. (1988). Introduction to NMR 
Spectroscopy, p. 196. New York: John Wiley. 
Gilmore, J. C. (1984). J. Appl. Cryst. 17, 42-46. 
Johnson, C. K. (1965). ORTEP. Report ORNL-3794. Oak Ridge Na- 
tional Laboratory, Tennessee, USA. 
McDowell, D. W. M. & Greenwood, T. D. (1965). J. Heterocycl. Chem. 
2, 44-48. 
Comment 
The recently isolated natural product aranorosin (1) dis- 
plays antibiotic, antifungal and antitumor properties (Roy, 
Mukhopadhyay, Reddy, Desikan, Rupp & Ganguli, 1988; 
Felhaber, Kogler, Mukhopadhyay, Vijayakumar, Roy, 
Rupp & Ganguli, 1988; Felhaber, Kogler, Mukhopad- 
hyay, Vijayakumar & Ganguli, 1988). The novel spiro- 
cyclic cyclohexanone diepoxide moiety of this molecule 
provides a particularly challenging synthetic target. This 
challenge, as well as the biological properties of ara- 
norosin (1), have stimulated interest in its synthesis 
(Rama Rao, Gurjar & Sharma, 1991) and a highly stereo- 
selective route to the model aranorosin ucleus (2) has 
© 1994 International Union of Crystallography 
Printed in Great Britain - all rights reserved 
Acta Crystallographica Section C 
ISSN 0108-2701 ©1994 


Synthesis and structure of <i>trans</i>-1,2,3- tris(3-thenoyl)cyclopropane

Abstract

Similar works

Full text

Available Versions

UnissResearch