Ales Gavenda

Bio: Ales Gavenda is an academic researcher from Ivax Corporation. The author has contributed to research in topics: Imatinib mesylate & Sunitinib malate. The author has an hindex of 9, co-authored 35 publications receiving 216 citations.

Polymorphs of dasatinib and process for preparation thereof

Abstract: Provided is dasatinib, solvates thereof and their crystalline forms, methods for their preparation, and pharmaceutical compositions thereof. Formula (I).

Polymorphic forms of imatinib mesylate and processes for their preparation as well as of amorphous imatinib mesylate and form alpha

Abstract: Solvates and crystalline forms of imatinib mesylate are described. Further, methods for preparing such solvates and crystalline forms of imatinib mesylate are described.

Imatinib base, and imatinib mesylate and processes for preparation thereof

Abstract: The present invention provides crystalline forms of imatinib base, imatinib base free of desmethyl imatinib, and imatinib mesylate free of desmethyl imatinib mesylate, processes of their preparation and pharmaceutical compositions of imatinib mesylate.

Capecitabine from X-ray powder synchrotron data.

Abstract: In the title compound [systematic name 5-de­oxy-5-fluoro-N-(pent­yloxycarbon­yl)cytidine], C15H22FN3O6, the pentyl chain is disordered over two positions with refined occupancies of 0.53 (5) and 0.47 (5). The furan ring assumes an envelope conformation. In the crystal, inter­molecular N—H⋯O hydrogen bonds link the mol­ecules into chains propagating along the b axis. The crystal packing exhibits electrostatic inter­actions between the 5-fluoro­pyrimidin-2(1H)-one fragments of neighbouring mol­ecules as indicated by short O⋯C [2.875 (3) and 2.961 (3) A] and F⋯C [2.886 (3) A] contacts.

Sunitinib hemi-l-malate, polymorphs and preparation thereof, polymorphs of racemic sunitinib malate, compositins containing sunitinib base and malic acid and preparation thereof

Abstract: The invention provides Sunitinib hemi-L-malate, polymorphs thereof, polymorphs of racemic sunitinib malate, compositions containing sunitinib base and either L or racemic malic acid, processes for the preparation thereof, and pharmaceutical compositions thereof.

Validation of molecular crystal structures from powder diffraction data with dispersion-corrected density functional theory (DFT-D).

Abstract: In 2010 we energy-minimized 225 high-quality single-crystal (SX) structures with dispersion-corrected density functional theory (DFT-D) to establish a quantitative benchmark. For the current paper, 215 organic crystal structures determined from X-ray powder diffraction (XRPD) data and published in an IUCr journal were energy-minimized with DFT-D and compared to the SX benchmark. The on average slightly less accurate atomic coordinates of XRPD structures do lead to systematically higher root mean square Cartesian displacement (RMSCD) values upon energy minimization than for SX structures, but the RMSCD value is still a good indicator for the detection of structures that deserve a closer look. The upper RMSCD limit for a correct structure must be increased from 0.25 A for SX structures to 0.35 A for XRPD structures; the grey area must be extended from 0.30 to 0.40 A. Based on the energy minimizations, three structures are re-refined to give more precise atomic coordinates. For six structures our calculations provide the missing positions for the H atoms, for five structures they provide corrected positions for some H atoms. Seven crystal structures showed a minor error for a non-H atom. For five structures the energy minimizations suggest a higher space-group symmetry. For the 225 SX structures, the only deviations observed upon energy minimization were three minor H-atom related issues. Preferred orientation is the most important cause of problems. A preferred-orientation correction is the only correction where the experimental data are modified to fit the model. We conclude that molecular crystal structures determined from powder diffraction data that are published in IUCr journals are of high quality, with less than 4% containing an error in a non-H atom.

Process for preparing azacytidine intermediate

Abstract: The present invention provides a processes for preparing 5-Azacytidine, and intermediates thereof. The present invention further provides an analytical method for determining the purity of 5-Azacytidine in a sample.