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The crystal and molecular structure of (4R, 5R)-4-(1', 2', 3', 4', 5'-penta-O-acetyl-D-manno-pentitol-1-yl)-5-[N-(4-methoxyphenyl)carbamoyl]-2-(N-methyl-benzylamino)-3-nitro-5-phenyl-4,5-dihydrothiophene {IUPAC name: 1-(2R,3R)-5-(N-benzyl-N-methylamino)-2-[N-(4-methoxyphenyl)carbamoyl]-4-nitro-2-phenyl-2,3-dihydro-3-thienyl]-1,2,3,4,5-penta-O-acetyl-D-manno-pentitol}, C 41 H 45 N 3 O 14 S, has been investigated at 150K. The analysis of the crystal structure allows the definition of the absolute configuration of the products of the cycloaddition reaction between 3,5-diphenyl-2-(N-methylbenzylamine)-1,3-thiazolium-7-olate and (E)-3,4,5,6,7-penta-O-acetyl-1,2-dideoxy-1-C-nitro-D-manno-hept-1-enitol, where only one of the two diastereoisomeric dihydrothiophenes could be isolated. The configurations at the new C4 and C5 stereocentres, with respect to that known at C6, are R,R. Except for a slight overall contraction and a slightly altered geometry of the terminal acetyl group, the structure is virtually the same as at room temperature.

The crystal structure of the title compound, C40H43N3O13S, has been determined at room temperature and at 150 K. From the cyclo­addition of thio­isomunchnones with chiral nitro­alkenes, two diastereomeric di­hydro­thio­phenes were obtained, showing that regiospecificity and facial selectivity were involved in these cyclo­additions reactions where only one of the two diastereomeric di­hydro­thio­phenes could be isolated in the solid state. The chiralities of the two new centres at C4 and C5, determined with respect to that known at C6 are R,R. N—H⋯O hydrogen bonds join the mol­ecules in chains running along the c axis.

The configurations around the chiral centres C53, C52, C51 and C5 are R, S, R and R, respectively, corresponding to a D-arabino conformation. The tetrahydrotetrazine ring has a conformation close to that of a half-boat. Packing of the molecules is governed by normal van der Waals contacts

The thiazolidine ring in the title compound has an envelope conformation, E 4 , with a C atom out of the plane of the ring. The C-S and C-N bond lengths clearly show the typical resonance of the thiourea group. The molecules are linked by van der Waals forces and an intramolecular N...N hydrogen bond is present

This work unambiguously establishes the overall conformation of the title molecule, C 36 H 37 N 3 O 9 S, which includes a thiirane ring. The configuration is α-D-glucofuranose with the furanosyl ring T 4 3 ; the imidazolidine-2-one group assumes a form in which the fused C2' atom deviates by 0.14 A from the best plane

C 8 H 11 NO 4 cristallise dans P1 avec a=5,277, b=8,872, c=10,123 A, α=102,86, β=90,07, γ=102,87°, Z=2; affinement jusqu'a R=0,080. A cause de l'effet «push-pull», la longueur de la liaison C=C est longue de 1,399 A et les angles de torsion autour de cette liaison sont de 176,8 et 0,5°. Le cycle 1,3-dioxane adopte une conformation demi bateau a cause des substituants en position equatoriale sur C(4) et C(6) et aussi a cause de la resonance

C 6 H 12 O 5 S cristallise dans P2 1 /c avec a=8,473, b=7,437, c=13,952 A, β=94,51°, Z=4; affinement jusqu'a R=0,038. Le cyclo oxathiane adopte une conformation chaise. Les deux substituants OCH 3 sont en positions trans. L'empilement des molecules est regi par des interactions de van der Waals

C 16 H 22 N 2 O 2 cristallise dans P2 1 /a avec a=14,253, b=9,994, C=10,468 A, Z=4, affinement jusqu'a R=0,06. La conformation du cycle piperidine est chaise. L'angle diedre entre les plans moindres carres du benzene et des heterocycles a 6 chainons est 56,7 o . La cohesion du cristal est realisee par des interactions de Van der Waals bien qu'il y ait egalement une liaison hydrogene faible intermoleculaire

C 24 H 28 N 2 O 10 cristallise dans P2 1 avec a=21,663, b=5,644, c=10,884A, β=102,06°, Z=2 , affinement jusqu'a R=0,072. L'angle diedre entre les cyles pyrazole et phenyl est de 25,9° ; entre le cycle pyrazole et la chaine galacto, il est de 57,5°. Les molecules sont liees par des forces de Van der Waals

C 11 H 11 N 3 O 2 cristallise dans P1 avec a=8,020, b=8,490, c=9,031 A, α=117,19, β=102,66 o , Z=2; affinement jusqu'a R=0,06. L'angle diedre entre le plan de l'imidazole et le cycle aromatique est de 55,3 o . Les liaisons doubles dans le cycle de l'imidazole sont delocalisees. Les molecules sont liees par des forces de van der Waals, mais il y a un contact court entre les atomes N de l'amine et O du carbonyle

The solid-state conformation of the title compound, C 23 H 29 NO 10 , has been unequivocally established. The configuration at C1 is β-D-glucopyranose and the pyranose ring is essentially a perfect chair. Only the E rotamer along the N-C bond is observed.

Crystallographic thermal parameters for the title compound are found with a lattice-dynamical calculation within the harmonic approximation and the external Born-von K~irm~in formalism using an atom-atom potential function in the form: V(r)=-A/r6+ B exp (-Cr), where the constants A, B and C have been taken from the literature. The agreement with experimental results is acceptable, R = 0.18.

C 25 H 33 NO 13 cristallise dans le systeme orthrhombique, groupe d'espace P2 1 2 1 2 1 et sa structure est affinee jusqu'a R=0,092