Crystal structure of a cholesterol-based dimesogen

The title compound, cholesteryl 6[4-(4-pentyloxyphenylethynyl)phenoxy]hexanoate (DMT5), a cholesterol-based dimesogen, crystallizes in the monoclinic space group P2₁ with the parameters a = 9.812(3) Å, b = 9.713(2) Å, c = 24.179(2) Å, β = 92.48(1)° V = 2302.2(9) ų, Z = 2, F₀₀₀ = 836, λ(MoK_α) = 0.71069 Å, μ = 0.067 cm 1, final R = 0.0772. The structure has intermolecular hydrogen bonds; it is stabilized by the presence of intermolecular contacts whose spacings are less than van der Waals' radii.     

Structural Conformation of a Novel Piperidine-4-One Derivative: 1-Acryloyl-3-Methyl-2,6-Dip-Tolylpiperidine-4-One

Abstract  

The novel 3-methyl-2,6-dip-toylpiperidine-4-one was acylated by 3-chloropropanoychloride and subjected for dehydrohalogenation. The synthesized compound was characterized by spectroscopic techniques and finally confirmed by X-ray diffraction studies. The molecule crystallizes in the monoclinic crystal class in the space group C ₂/c with cell parameters a = 18.538(2) ?, b = 9.9050(1) ?, c = 22.954(2) ?, β = 94.486(8)° and Z = 8. The piperidine ring adopts a twist boat conformation.     

A concise synthetic strategy to functionalized chromenones via [5+1] heteroannulation and facile C-N/C-S/C-O bond formation with various nucleophiles

A highly efficient strategy to 2,3-substituted chromen-4H-ones has been developed. The methodology involves unexpected intramolecular heteroannulation of readily accessible substituted 2-hydroxy-ω-nitroacetophenone with carbon disulfide in the presence K₂CO₃ followed by methylation with methyl iodide. These chromenones were further reacted with various nucleophiles such as amines, thiols, and alkoxide resulting in the facile C-N, C-S, and C-O bond formation. The scope and generality have been discussed.     

Theory of sheath in a collisional multi-component plasma

The aim of this brief report is to study the behaviour of sheath structure in a multi-component plasma with dust-neutral collisions. The plasma consists of electrons, ions, micron size negatively charged dust particles and neutrals. The sheath-edge potential and sheath width are calculated for collisionally dominated sheath. Comparison of collisionless and collisionally dominated sheath are made.     

Miscibility studies on blends of cellulose acetate and nylon 6

Miscibility studies on cellulose secondary acetate(CA)/Nylon 6(N6) blends have been carried out in this work. Dilute solution viscometry for the blend solutions using formic acid as the common solvent shows the existence of miscibility window.     

Spin squeezing and quantum correlations

We discuss the notion of spin squeezing considering two mutually exclusive classes of spin-s states, namely, oriented and non-oriented states. Our analysis shows that the oriented states are not squeezed while non-oriented states exhibit squeezing. We also present a new scheme for construction of spin-s states using 2s spinors oriented along different axes. Taking the case of s=1, we show that the ‘non-oriented’ nature and hence squeezing arise from the intrinsic quantum correlations that exist among the spinors in the coupled state.     

Synthesis and molecular structure analysis of venlafaxine intermediate and its analog

1-(cyano-(4-methoxyphenyl) methyl cyclohexanol(2), C₂₄H₃₂N₂O₂, a Venlafaxine intermediate is found to crystallize in both monoclinic(2a) and orthorhombic(2b) crystal systems. The form2a crystallizes in the space groupC2/c with the cell parametersa = 23.506(3),b = 5.550(3),c = 23.192(3), and β = 115.116(2)^∘.2b crystallizes in space groupP2₁2₁2₁ with cell parametersa = 5.7850(6),b = 11.2680(6), andc = 20.6730(19). The intermolecular hydrogen bonding in the case of the monoclinic polymorph leads to the formation of dimer. The synthesis, characterization, and crystal structure studies of Venlafaxine analog 1-[2-1-(4-dimethylamino-phenyl)-ethylideneamino]-1-(4-methoxy-phenyl)-ethyl]-cyclohexanol(4) is reported.4 crystallizes inP―1 space group with cell parametersa = 10.801(7),b = 12.078(7),c = 9.928(5), α = 96.12(5)^∘, β = 110.49(5)^∘, and γ = 112.42(6)^∘.     

Structural Conformation of a Novel 1-Benzhydrylpiperazine Derivative: 1-Benzhydryl-4-(toluene-4-sulfonyl)-piperazine

Abstract  The title compound 1-benzhydryl-4-(toluene-4-sulfonyl)-piperazine was synthesized and the structure was investigated by X-ray crystallography. The title compound, C₂₄H₂₆N₂O₂S crystallizes in the monoclinic crystal class in the space group P2₁/c with cell parameters a = 13.5800(10) ?, b = 8.9630(7) ?, c = 18.9040(10) ?, β = 106.851(3)°, Z = 4 and V = 2202.1(3) ?³. The structure has been solved by direct methods and refined to R ₁ = 0.0468 for 3174 observed reflections I > 2σ(I). The structure reveals that the piperazine ring is in a chair conformation. The geometry around the S atom is a distorted tetrahedron. Graphical Abstract  The title compound 1-benzhydryl-4-(toluene-4-sulfonyl)-piperazine was synthesized and the structure was investigated by X-ray crystallography. The title compound, C₂₄H₂₆N₂O₂S crystallizes in the monoclinic crystal class in the space group P2₁/c with cell parameters a = 13.5800(10) ?, b = 8.9630(7) ?, c = 18.9040(10) ?, β = 106.851(3)°, Z = 4 and V = 2202.1(3) ?³. The structure has been solved by direct methods and refined to R ₁ = 0.0468 for 3174 observed reflections I > 2σ(I). The structure reveals that the piperazine ring is in a chair conformation. The geometry around the S atom is a distorted tetrahedron.

Synthesis and Crystal Structure Studies of Novel Bioactive Heterocycle: 7-Chloro-5-Cyclopropyl-9-Methyl-10-(2-Piperidin-1-yl-Ethyl)-5,10-Dihydro-4,5,6,10-Tetraaza-Dibenzo[a,d] Cyclohepten-11-One

Abstract  The compound, 7-chloro-5-cyclopropyl-9-methyl-10-(2-piperidin-1-yl-ethyl)-5,10-dihydro-4,5,6,10-tetraaza-dibenzo[a, d] cyclohepten-11-one, C₂₂H₂₆N₅ClO, crystallizes in the triclinic space group Pī with cell parameters a = 8.918(7) ?, b = 9.297(7) ?, c = 14.184(8) ?, V = 1095.98(1) ?³ and Z = 2. The final residual factor R ₁ = 0.0451. The structure exhibits intermolecular hydrogen bonds. The 2-piperidin-1-yl-ethyl ring adopts a chair conformation. The starting material used to synthesize the title compound is the intermediate compound of well known anti-HIV drug Nevirapine hence the title compound is having biological importance and hence this crystal structure will helps to structural characterization of the molecule and also for the molecular modeling it will helps for biological study. Graphical Abstract  The title compound 7-chloro-5-cyclopropyl-9-methyl-10-(2-piperidin-1-yl-ethyl)-5,10-dihydro-4,5,6,10-tetraaza-dibenzo[a, d] cyclohepten-11-one was synthesized by condensation of 7-chloro-5-cyclopropyl-9-methyl-5,10-dihydro-4,5,6,10-tetraaza-dibenzo[a, d] cyclohepten-11-one with 1-(2-chloro-ethyl)-piperidine hydrochloride in presence of anhydrous powdered potassium carbonate as base using N,N-dimethyl formamide as solvent and its crystal structure determined. The title compound derived from bioactive molecule and it is also having biological importance hence this crystal structure will helps for the structural characterization and the biological study of the novel molecule.      

Synthesis of polyhydroxy piperidines and their analogues: a novel approach towards selective inhibitors of alpha-glucosidase

Various polyhydroxy piperidine azasugars have been synthesized from precursors 18a and 18b, obtained in both enantiomeric forms from d-ribose. Out of these polyhydroxy piperidine azasugars, 22, 39 and 20 were found to be potent as well as selective inhibitors of alpha-glucosidase with K(i) values ranging as low as 1.07 microM, 16.4 microM, and 88.2 microM, respectively. Replacement of the hydroxy methylene moiety of (K(i) 33% at 1 mM) by an amino methylene moiety (32, K(i) 36.8 microM) showed a remarkable increase in the activity (almost 30 times). Furthermore, increasing the lipophilicity of by N-alkylation with a dodecyl group (36) showed a three-fold enhancement in the activity (K(i) 217 microM to K(i) 72.3 microM).