35 research outputs found
Lewis Acid‐Catalyzed Stereoselective α‐Addition of Chiral Aldehydes to Cyclic Dienol Silanes: Aqueous Synthesis of Chiral Butenolides
No full textAn Improved Stereocontrolled Access Route to Piperidine or Azepane β-Amino Esters and Azabicyclic β- and γ- Lactams; Synthesis of Novel Functionalized Azaheterocyles
No full textOne–Pot Synthesis of β,γ-Unsaturated γ-Lactone Phosphorus Yildes using 2-Nitro Trans-Cinnamaldehyde and Acetylenic Esters in the Presence of Triphenylphosphine
No full textRetraction of “Crystallization Engineering in Aza-Steroid: Application in the Development of Finasteride”
No full textAn Improved Stereocontrolled Access Route to Piperidine or Azepane β‐Amino Esters and Azabicyclic β‐ and γ‐Lactams; Synthesis of Novel Functionalized Azaheterocyles
No full text
Biocatalytic Asymmetric Reduction of γ‐Keto Esters to Access Optically Active γ‐Aryl‐γ‐butyrolactones
No full text
Structural insights into the ene-‐reductase synthesis of Profens
Get PDFReduction of double bonds of α,β-unsaturated carboxylic acids and esters by ene-reductases remains challenging and it typically requires activation by a second electron-withdrawing moiety, such as a halide or second carboxylate group. We showed that profen precursors, 2-arylpropenoic acids and their esters, were efficiently reduced by Old Yellow Enzymes (OYEs). The XenA and GYE enzymes showed activity towards acids, while a wider range of enzymes were active towards the equivalent methyl esters. Comparative co-crystal structural analysis of profen-bound OYEs highlighted key interactions important in determining substrate binding in a catalytically active conformation. The general utility of ene reductases for the synthesis of (R)-profens was established and this work will now drive future mutagenesis studies to screen for the production of pharmaceutically-active (S)-profens
Identification and Characterization of Potential Impurities of Dronedarone Hydrochloride
No full textSix
potential process related impurities were detected during the
impurity profile study of an antiarrhythmic drug substance, Dronedarone
(<b>1</b>). Simple high performance liquid chromatography and
liquid chromatography–mass spectrometry methods were used for
the detection of these process impurities. Based on the synthesis
and spectral data (MS, IR, <sup>1</sup>H NMR, <sup>13</sup>C NMR,
and DEPT), the structures of these impurities were characterized as
5-amino-3-[4-(3-di-<i>n</i>-butylaminopropoxy)benzoyl]-2-<i>n</i>-butylbenzofuran (impurity I); <i>N</i>-(2-butyl-3-(4-(3-(dibutylamino)propoxy)benzoyl)benzofuran-5-yl)-<i>N</i>-(methylsulfonyl)methanesulfonamide (impurity II); <i>N</i>-(2-butyl-3-(4-(3-(dibutylamino)propoxy)benzoyl)benzofuran-5-yl)-1-chloromethanesulfonamide
(impurity III); <i>N</i>-{2-propyl-3-[4-(3-dibutylaminopropoxy)benzoyl]benzofuran-5-yl}methanesulfonamide
(impurity IV); <i>N</i>-(2-butyl-3-(4-(3-(dibutylamino)propoxy)benzoyl)benzofuran-5-yl)formamide
(impurity V); and (2-butyl-5-((3-(dibutylamino)propyl)amino)benzofuran-3-yl)(4-(3-(dibutylamino)propoxy)phenyl)methanone
(impurity VI). The synthesis and characterization of these impurities
are discussed in detail
