27489-60-7Relevant articles and documents
Overcoming Problems at Elaboration and Scale-up of Liquid-Phase Pd/C Mediated Catalytic Hydrogenations in Pharmaceutical Production
Tungler, Antal,Szabados, Erika
, p. 1246 - 1251 (2016)
The practical solutions for scale-up and production of intermediates or precursors of pharmaceuticals by liquid-phase Pd/C mediated hydrogenation can be of considerable interest and deserve broader attention even if they have not been the focus of previously published research due to regulations of patent law. The practical obstacles are persistent and have been known for a long time, but for the most part remained unpublished. The most important discoveries and solutions that contributed to the successful scale-up of hydrogenations for pharmaceutical production were the following: (i) the poisoning of Pd/C catalyst with Fe2+ ions for the selective hydrogenation of 2,6-dimethyl-1-nitrosopiperidine to the corresponding hydrazo compound; (ii) alloying of the deposited Pd metal with Cu for converting the aromatic acid chlorides into the corresponding aldehydes; (iii) alteration of the pH of the reaction mixture to basic values which enhanced the stereoselectivity of paracetamol hydrogenation; (iv) a useful modification of the catalyst preparation process, i.e., the acidification of the catalyst resulted in the hydrogenolysis of benzylic OH in a molecule containing a basic N atom; (v) use of two liquid phases, altogether a four-phase system, which permitted the hydrogenolysis of the S-S bond in a potential catalyst poisoning molecule; (vi) the preservation of the metallic Pd surface of the catalyst by saturation of the reaction mixture with hydrogen, resulting in a high H2/substrate ratio, increased the aldehyde yield in the hydrogenation of 4-chloro-butyric-acid-chloride by avoiding the unwanted poisoning effect of the hydrochloric acid. In the present article, these problems and their solutions, as they emerged during the scale-up of the processes, will be discussed in detail.
ISOTOPE ENHANCED AMBROXOL FOR LONG LASTING AUTOPHAGY INDUCTION
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Page/Page column 21-22, (2018/09/08)
The present invention is directed to 13C and/or 2H isotope enhanced ambroxol ("isotope enhanced ambroxol") and its use in the treatment of autophagy infections, especially mycobacterial and other infections, disease states and/or conditions of the lung, such as tuberculosis, especially including drug resistant and multiple drag resistant tuberculosis. Pharmaceutical compositions comprising isotope enhanced amhroxol, alone or in combination with an additional bioactive agent, especially rifamycin antibiotics, including an additional autophagy modulator (an agent which is active to promote or inhibit autophagy), thus being useful against, an autophagy mediated disease state and/or condition), especially an antophagy mediated disease state and/or condition which occurs in the lungs, for example, a Mycobacterium infection. Chronic Obstructive Pulmonary Disease (COPD), asthma, pulmonary fibrosis, cystic fibrosis, Sjogren's disease and lung cancer (small cell and non-small cell lung cancer, among other disease states and/or conditions, especially of the lung. Methods of treating autophagy disease states and/or conditions, especially including autophagy disease states or conditions which occur principally in the lungs of a patient represent a further embodiment of the present invention. An additional embodiment includes methods of synthesizing compounds according to the present invention as otherwise disclosed herein.
CMP and CMP-sugar analogs as inhibitors of sialic acid incorporation into glycoconjugates
Korytnyk,Angelino,Klohs,Bernacki
, p. 77 - 84 (2007/10/02)
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