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1.
The title compounds, (3R,5S,5′R,8R,9S,10S,13S,14S)‐10,13‐dimethyl‐5′‐(2‐methylpropyl)tetradecahydro‐6′H‐spiro[cyclopenta[a]phenanthrene‐3,2′‐[1,4]oxazinane]‐6′,17(2H)‐dione, C26H41NO3, (I), and methyl (2R)‐2‐[(3R,5S,8R,9S,10S,13S,14S)‐10,13‐dimethyl‐2′,17‐dioxohexadecahydro‐3′H‐spiro[cyclopenta[a]phenanthrene‐3,5′‐[1,3]oxazolidin‐3′‐yl]]‐4‐methylpentanoate, C28H43NO5, (II), possess the typical steroid shape (AD rings), but they differ in their extra E ring. The azalactone E ring in (I) shows a half‐chair conformation, while the carbamate E ring of (II) is planar. The orientation of the E‐ring substituent is clearly established and allows a rationalization of the biological results obtained with such androsterone derivatives.  相似文献   

2.
The double addition of organometallic reagents to fused oxazino-oxazines prepared from glyoxal and (S)-phenylglycinol afforded C2- or C1-symmetric 1,2-ethylenebis(β-aminoalcohols), depending on the nature of the organometallic reagent. This route was modified by the use of (S)-valinol and phenylglyoxal as starting materials, and by reduction of the oxazino-oxazines by diborane. Cyclization of the β-aminoalcohol moieties gave 1,2-ethylenediaziridines bearing one substituent/stereocenter on the ring carbon and one, two or no substituents/stereocenters in the ethylene tether. These bis(aziridines) were used as ligands in the Pd-catalyzed allylic alkylation of dimethyl malonate. It was established that the substituent(s) in the carbon tether and the configuration of the corresponding stereocenters have limited influence on the enantioselectivity.  相似文献   

3.
By reaction of (C5H5)2Ti(μ-S2)2C6H10 3 with S2Cl2 7,8,9,10,11,12-hexathiaspiro-[5.6]dodecane 4 is prepared (yield 51%) and characterized by UV, IR, Raman, mass, and NMR spectra (1H, 13C). The seven-membered CS6 ring undergoes pseudorotation in solution. With S7Cl2 the complex 3 yields 7,8,9,10,11,12,13,14,15,16,17-undecathiaspiro[5.11]heptadecane 5 (yield 23%). The yellow, monoclinic crystals of 5 consist of spirocyclic C6H10S11 molecules with the C6 ring in a chair-conformation while the CS11 ring is of the same conformation as cyclododecasulfur S12. UV, IR, Raman, mass and NMR-spectra of 5 are reported. A mixture of dichlorosulfanes SnCl2 (n = 1 -8) reacts with 3 to give the homologous series C6H10Sm which was characterized by reversed-phase HPLC for m = 5 – 14.  相似文献   

4.
In the title compound, C24H17NO2S, the dioxine and thia­zoline rings are distorted from planarity towards a half‐chair and an envelope conformation, respectively. The configurations of the dioxine ring, the thiazoline ring and the attached phenyl ring are conditioned by the sp3 state of the two bridgehead C atoms. The phenanthrene system is nearly coplanar with the dioxine ring, while the attached phenyl ring is orthogonal to the thia­zoline ring.  相似文献   

5.
The hydrogen abstraction/acetylene addition (HACA) mechanism has long been viewed as a key route to aromatic ring growth of polycyclic aromatic hydrocarbons (PAHs) in combustion systems. However, doubt has been drawn on the ubiquity of the mechanism by recent electronic structure calculations which predict that the HACA mechanism starting from the naphthyl radical preferentially forms acenaphthylene, thereby blocking cyclization to a third six‐membered ring. Here, by probing the products formed in the reaction of 1‐ and 2‐naphthyl radicals in excess acetylene under combustion‐like conditions with the help of photoionization mass spectrometry, we provide experimental evidence that this reaction produces 1‐ and 2‐ethynylnaphthalenes (C12H8), acenaphthylene (C12H8) and diethynylnaphthalenes (C14H8). Importantly, neither phenanthrene nor anthracene (C14H10) was found, which indicates that the HACA mechanism does not lead to cyclization of the third aromatic ring as expected but rather undergoes ethynyl substitution reactions instead.  相似文献   

6.
In the title compound, C17H12S5, the di­thiole ring bearing the aryl substituents assumes an envelope conformation with the maximum deviation from planarity being −0.053 Å. The phenyl and benzyl rings are twisted by 33.0 (1) and 31.1 (1)°, respectively, out of the di­thiole plane. The crystal packing is governed by short S⃛S interactions, with the shortest being 3.550 (2) Å.  相似文献   

7.
Two of the 12 possible oxide-bridged phenylmorphans, were synthesized, rac-(3R,6aS,11aS)-2-methyl-1,3,4,5,6,11a-hexahydro-2H-3,6a-methanobenzofuro[2,3-c]azocine-10-ol (7) (the ortho-c compound), and rac-(3R,6aS,11aS)-2-methyl-1,3,4,5,6,11a-hexahydro-2H-3,6a-methanobenzofuro[2,3-c]azocine-8-ol (8) (the para-c compound). Single-crystal X-ray diffraction studies indicated that the dihedral angle between the least squares planes through the phenyl ring and the atoms C1, C11a, C12, and C3 in the piperidine ring in both 7·CHCl3 and 8·HBr was 6.9°. The C12-C6a-C6b-C10a torsion angle was found to be 139.3° for both compounds. The angular relationship between the phenolic ring and the piperidine ring in phenylmorphans that interact with specific opioid receptors as agonists or antagonists is of considerable theoretical interest.  相似文献   

8.
Model chemistry G3(MP2,CC)//B3LYP/6-311G(d,p) calculations of the potential energy surface for the reaction of phenyl radical (C6H5) with phenylacetylene (C8H6) have been carried out and combined with Rice-Ramsperger-Kassel-Marcus/Master Equation calculations of temperature- and pressure-dependent rate constants. The results showed that the reaction can serve as a viable source for the formation of phenanthrene via an indirect route involving a primary reaction of phenyl addition to the ortho carbon in the ring of phenylacetylene and H elimination producing 2-ethynylbiphenyl followed by secondary H-assisted isomerization of 2-ethynylbiphenyl to phenanthrene. In the secondary reaction, the H atom adds to the α carbon of the ethynyl side chain, then a six-member ring closure takes place followed by aromatization via an H loss. The channel of H addition to the side chain of 2-ethynylbiphenyl appears to be much faster than H addition to the ortho carbon in the ethynyl-substituted ring leading back to the initial C6H5 + C8H6 reactants. Rate constants for the primary C6H5 + C8H62-ethynylbiphenyl ( p1 ) + H and secondary p1  + Hphenanthrene ( p2 ) + H reactions have been computed in the temperature range of 500-2500 K at pressures of 30 Torr, 1, 10, and 100 atm and fitted to modified Arrhenius expressions. The suggested kinetic scheme and rate constants are proposed as a prototype for the modeling of the growth of polycyclic aromatic hydrocarbons via the phenyl addition-dehydrocyclization (PAC) mechanism involving an addition of a PAH radical to an ethynyl-substituted PAH molecule.  相似文献   

9.
In the title compounds, C24H17NO3, (I), and C43H27NO5, (II), the dioxine ring is not planar and tends toward a boat conformation. The oxazoline ring adopts a twisted conformation in mol­ecule (I) but is essentially planar in mol­ecule (II). The configuration of the dioxine–oxazoline system is determined by the sp3 state of the two shared atoms. The phenanthrene moiety is nearly coplanar with the dioxine ring, while the phenyl ring is perpendicular to the attached oxazole ring. The triclinic unit cell of (II) contains two crystallographically independent mol­ecules related by a pseudo‐inversion centre.  相似文献   

10.
The mol­ecules of di­spiro­[1,3‐dithietane‐2,2′:4,2′′‐diadamantane], C20H28S2, have crystallographic Ci symmetry, as well as local D2h symmetry, and a planar 1,3‐dithietane ring. The mol­ecules of tri­spiro­[1,3,5‐tri­thia­ne‐2,2′:4,2′′:6,2′′′‐triadamantane], C30H42S3, have approximate C2 symmetry and the 1,3,5‐tri­thia­ne ring has a twist–boat conformation. The C—S—C bond angles within the ring are about 8° larger than observed in most related 1,3,5‐tri­thia­ne structures. In di­spiro­[1,2,4‐tri­thiol­ane‐3,2′:5,2′′‐diadamantane], C20H28S3, the mol­ecules have local C2 symmetry and the 1,2,4‐tri­thiol­ane ring has a half‐chair conformation.  相似文献   

11.
The title potentially tetradentate N,S,S,N‐donor ligand, C26H20N2S2, has been structurally characterized. The two S atoms adopt a trans conformation, lying above and below the benzene ring. The two quinoline rings are planar, with one parallel to the benzene ring and the other nearly perpendicular to it.  相似文献   

12.
Titanium(IV) alkyl xanthates of the types CpTi(S2COR)Cl2, CpTi(S2COR)2Cl and CpTi(S2COR)3, where R = CH3, C2H5, C3H7, C4H9 and C5H11, have been prepared by the reaction of monocyclopentadienyl titanium(IV) trichloride with potassium alkyl xanthates in anhydrous dichloromethane. Conductance and infrared studies suggest that these complexes are non-electrolytes in which all of the xanthate ligands are bidentate. Proton nmr spectra of these complexes indicate that there is rapid rotation of the cyclopentadienyl ring about the metal-ring axis and for the CpTi(S2COR)3 complexes non-equivalence of the alkylxanthate ligands was observed.  相似文献   

13.
Methods of molecular mechanics were applied to investigate the conformation of the (methyl 2-O-sulfate-4-methyl-α-L-idopyranose) uronic acid (DMIS), in order to correlate the peculiar vicinal proton coupling constants observed in polysaccharides containing the iduronate ring to the conformational characteristics of this sugar ring. We found three conformers with comparable energies, namely the two chair forms 1C4 and 4C1 and the skew-boat form 2S0(L); the latter is separated from each chair form by a barrier of about 9 kcal/mol. Along the pseudorotational path three additional minima (3S1, 1S3, and 1S5) were found, yet at least 4 kcal/mol higher than 2S0. The results obtained for the relative energies of the three conformers and the conformation of the side groups were affected by the inclusion of the electrostatic term and, in particular, by the charge assigned to the ionic groups of DMIS. However, the conformational properties of the idopyranosidic ring in DMIS (and in related compounds) should still be interpreted in terms of equilibrium among these three conformers only.  相似文献   

14.
The aromatic [CpCo(S2C2(R)(H))] (R = Ph, Me, 9-phenanthryl, H) complexes reacted with N-halosuccinimides (NXS; X = Cl, Br, I) in carbon tetrachloride at room temperature to undergo the N-succinimide substitution reaction on the dithiolene ring, but no halogenated dithiolene complex was obtained. The imidation products [CpCo(S2C2(R)(N-sccinimide))] were yielded up to 64% where X = I and R = 9-phenanthryl. The reaction of [CpCo(S2C2(Ph)(H))] with N-bromophthalimide (NBP) also gave the imidation product [CpCo(S2C2(Ph)(N-phthalimide))]. This is the rare direct imidation reaction to an aromatic metallacycle by NXS. The reaction of [CpCo(S2C2H2)] (R = H) with NIS afforded the double imidation product. One by-product in this reaction was the dithiolene-dithiolene homo-coupling product [CpCo(S2C2(R))]2 (R = Ph, Me, 9-phenanthryl). The microwave-enhanced (MW) reactions were attempted in the carbon tetrachloride solution. Although the solution temperature increased up to only 43 °C by MW irradiation, the imidation reaction worked with short reaction time.  相似文献   

15.
Phosphorylation of 2-hydroxyphenyl 2,2,2-trifluoro-1-hydroxy-1-(trifluoromethyl)ethyl ketone with dichloro(phenyl)phosphine gave 5-oxo-2-phenyl-4,4-bis(trifluoromethyl)-4,5-di-hydro-1,3,2-benzodioxaphosphepine. Heating of the latter initiated an intramolecular interaction of the P atom with the carbonyl group. Hydrolysis of the intermediate product yielded 3-hydroxy-2-oxo-2-phenyl-3-[2,2,2-trifluoro-1-hydroxy-1-(trifluoromethyl)ethyl]-2,3-di-hydro-1,2λ5-benzo[d]oxaphosphole. The reaction was highly stereoselective (PRCS/PSCR). The reaction of the starting phosphepine with chloral proceeded highly stereoselectively (PRCSCS/PSCRCR) to give a 5-carbaphosphatrane derivative containing a four-membered ring, namely, 1-phenyl-3-trichloromethyl-10,10-bis(trifluoromethyl)-6,7-benzo-2,4,8,9-tetraoxa-1λ5-phosphatricyclo[3.3.2.01,5]decene. The trigonal bipyramid of the 5-carbaphosphatrane derivative is made up of the equatorial O atoms and the apical C atoms.  相似文献   

16.
Searches for new tuberculostatic agents are important considering the occurrence of drug‐resistant strains of Mycobacterium tuberculosis . The structures of three new potentially tuberculostatic compounds, namely isopropyl methyl (2‐hydroxybenzoyl)carbonohydrazonodithioate, C12H16N2O2S2, (Z )‐benzyl methyl (2‐hydroxybenzoyl)carbonohydrazonodithioate, C16H16N2O2S2, and dibenzyl (2‐hydroxybenzoyl)carbonohydrazonodithioate propan‐2‐ol monosolvate, C22H20N2O2S2·C3H8O, were determined by X‐ray diffraction. The mutual orientation of the three main fragments of the compounds, namely an aromatic ring, a dithioester group and a hydrazide group, can influence the biological activity of the compounds. In all three of the structures studied, the C(=O)NH group is in the anti conformation. In addition, the presence of the hydroxy group in the ortho position of the aromatic ring in all three structures leads to the formation of an intramolecular hydrogen bond stabilizing the planarity of the molecules.  相似文献   

17.
The title compound, 4‐methoxy‐2‐[(1S,2R,3S,4S,5R)‐3,4,5,6‐tetrahydro‐3,4,5‐tri­hydroxy‐6‐(hydroxy­methyl)‐2H‐­pyran‐2‐yl]‐α‐resorcylic acid δ‐lactone monohydrate, C14H16O9·H2O, is a C‐glucoside of 4‐O‐methylgallic acid which has antiasthmatic, antitussive, anti‐inflammatory, antifungal, anti‐HIV and antihepatotoxic activity. The mol­ecule is composed of three six‐membered rings: an aromatic ring, a glucopyran­ose ring and an annellated δ‐lactone ring. The glucopyran­ose ring exhibits only small deviations from an ideal chair conformation. The annellated δ‐lactone ring possesses the expected half‐chair conformation. There is one intra‐ and six intermolecular hydrogen bonds which form an extensive hydrogen‐bonding network within the crystal.  相似文献   

18.
The title compound, C15H20O4S2, crystallizes in a chiral space group although it contains mirror symmetry. The tropone ring is inclined at an angle of 50.3 (1)° to the crown ether ring. The planarity of the tropone ring system itself is diminished by as much as 20.8 (4)°.  相似文献   

19.
In the crystal structure of the title compound, C3H3NO2S2, the four‐membered C2S2 ring is planar, as is the whole mol­ecule. The short intramolecular S?O distance of 2.687 (2) Å shows the five‐atom system to be conjugated. The mol­ecules pack as a two‐dimensional network in the (010) plane through short intermolecular S?O [2.900 (2) and 3.077 (2) Å] interactions.  相似文献   

20.
Crystal and Molecular Structure, of S4N4 · 2C7H8 The structure of the title compound has been determined from threedimensional X-ray data. Crystals are monoclinic, with unit cell dimenions a = 16.532 Å, b = 8.563 Å, c = 10.880 Å, β = 103.2°, space group C? C2/c and Z = 4. Least squares refinement, by use of 1132 independent reflections measured on a diffractometer has reached 3.9%. In the S4N4·2C7H8 molecules the organic components are linked to two sulfur atoms of the S4N4, ring each.  相似文献   

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