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Oxime-carboxyl hydrogen bonds: the preferred interaction determining crystal packing. II. Crystal structure of 5beta-Cholanic acid 3-oxime

100%

Maurin J. K.

Polish Journal of Chemistry

1998

tom Vol. 72, nr 4

786-792

Beta-Cholanic acid oxime, C24H39NO3, M(r)=389.56, hexagonal, P6(5), a=b=14.564(3)A, c=20.282(5)A, alpha=beta=90 degree, gamma=120 degree, V=3725.7(14)A(3), Z=6. Crystal structure is composed from infinite hydrogen bonded chains of molecules forming bihelical arrangements along sixfold screw axes. Oxime-carboxyl hydrogen bonds are observed. Structure is both chiral and polar.

Reaction of phenyllithium with N-pivaloyl-20-piperidone

51%

Maurin J. K. , Czarnocki Z. , Burdach A.

Polish Journal of Chemistry

1998

tom Vol. 72, nr 5

940-948

Structural features of the reaction of N-pivaloyl-2-piperidone with phenyllithium were elaborated. Two compounds (4) and (5) were obtained and their structures were established by X-ray analysis. C16H23NO2(4): monoclinic, C2/c, a=37,197(7), b=8.479(2), c=9.988(2) A, beta=96.5(3)degree, Z=8; C22H27NO (5): orthorhombic, P2-12-12-1, a=8.244(2), b=10.305(2), c=22.616(5) A, Z=4.

Synthesis and Crystal Structure of Hydrogenated Pyrazino[2,1-a]isoquinoline Derivatives

38%

Zawadzka A. , Leniewski A. , Maurin J. K. , Wojtasiewicz K. , Siwicka A. , Czarnocki Z.

tom Vol. 77 / nr 5

565-576

Areview of the experimental as well as of the theoretical studies, performed on the area of the infrared spectroscopy of hydrogen bonded molecular crystals, is given. Discussion of some physical phenomena is presented, responsible for basic spectral effects registered in the infrared spectra, as breaking of vibrational dipole selection rules in the IR spectra, linear dichroic as well as temperature effects, observed in the frequency range of the proton stretching vibrations. Also some newly recognized H/D isotopic effects for hydrogen bonded systems are presented, deduced from a quantitative analysis of the polarized spectra in the IR, namely the so called isotopic "self-organization" effects and the "long-range" H/D isotopic effects.

The Suzuki-Miyaura reaction in the chemical transformations of vindoline

38%

Ruszkowska J. , Chrobak R. , Zero P. , Maurin J. K. , Szawkalo J. , Czarnocki Z.

Acta Biochimica Polonica

2007

tom 54

nr 4

857-861

Vindoline and its analogues are important constituents of the Madagascan periwinkle Catharanthus roseus, and some of them are valuable chemotherapy drugs used in treatment for some types of cancer, including leukaemia, lymphoma, breast and lung cancer. The search for semi-synthetic congeners of natural substances is still an important task for organic chemistry. In this communication we report the synthesis of five new vindoline derivatives, 15-(2-methoxyphenyl)vindoline 11, 15-(3-methoxyphenyl)vindoline 12, 15-(2-nitrophenyl)vindoline 13, 15-(3-cyanophenyl)vindoline 15, and 15-(4-cyanophenyl)vindoline 16 using the Suzuki-Miyaura reaction as the key step. X-Ray analysis of compound 16 is also reported