Richard J. Varsolona
Boehringer Ingelheim
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Publication
Featured researches published by Richard J. Varsolona.
Organic Letters | 2013
Xudong Wei; Chutian Shu; Nizar Haddad; Xingzhong Zeng; Nitinchandra D. Patel; Zhulin Tan; Jianxiu Liu; Heewon Lee; Sherry Shen; Scot Campbell; Richard J. Varsolona; Carl A. Busacca; Azad Hossain; Nathan K. Yee; Chris H. Senanayake
A highly convergent large scale synthesis of a 15-membered macrocyclic hepatitis C virus (HCV) protease inhibitor BI 201302 was achieved, in which the key features are the practical macrocyclization by Ru-catalyzed ring-closing metathesis (0.1 mol % Grela catalyst, 0.1-0.2 M concentration) and the efficient sulfone-mediated SNAr reaction.
Journal of Pharmaceutical and Biomedical Analysis | 2010
Nina C. Gonnella; John A. Smoliga; Scot Campbell; Carl A. Busacca; Michael Kenneth Cerreta; Richard J. Varsolona; Daniel L. Norwood
A novel inhibitor of reverse transcriptase was studied by solid-state NMR. Three phases of the compound were examined which included the dihydrate and two anhydrous polymorphs (Form I and Form III). By correlating (1)H and (13)C solution NMR with the solid-state (13)C NMR CP/MAS and CPPI spectral editing experiments, comparative (13)C assignments were made for each phase. Polymorphs of Form I and Form III and the dihydrate were easily distinguished based upon chemical shift patterns of the carbon resonances. The (1)H spin-lattice relaxation times were also measured for each phase which provided information on the mobility and relative crystallinity. The (13)C ssNMR spectrum of Form I showed the presence of a minor component identified as the dihydrate. Weight/percent quantitation of major and minor components in Form I was obtained from integrated intensities of a 50:50 mixture containing weighed amounts of Form I and the pure dihydrate. Comparison of the ssNMR and X-ray powder diffraction techniques is discussed.
Organic Letters | 2005
Carl A. Busacca; Jon C. Lorenz; Nelu Grinberg; Nizar Haddad; Matt Hrapchak; Bachir Latli; Heewon Lee; Paul Sabila; Anjan Saha; Max Sarvestani; Sherry Shen; Richard J. Varsolona; Xudong Wei; Chris H. Senanayake
Archive | 2011
Michael Kenneth Cerreta; John A. Smoliga; Richard J. Varsolona
Tetrahedron Letters | 2008
Frank Roschangar; Jianxiu Liu; Emilie Estanove; Marine Dufour; Sonia Rodriguez; Vittorio Farina; Eugene R. Hickey; Azad Hossain; Paul-James Jones; Heewon Lee; Bruce Z. Lu; Richard J. Varsolona; Jürgen Schröder; Pierre L. Beaulieu; James Gillard; Chris H. Senanayake
Tetrahedron Letters | 2005
Xiao-Jun Wang; Li Zhang; Yibo Xu; Dhileepkumar Krishnamurthy; Richard J. Varsolona; Laurence J. Nummy; Sherry Shen; Rogelio P. Frutos; Denis Byrne; J.C. Chung; Vittorio Farina; Chris H. Senanayake
Organic Process Research & Development | 2012
Jeffrey B. Sperry; Roger Farr; Mahmut Levent; Mousumi Ghosh; Steven M. Hoagland; Richard J. Varsolona; Karen Sutherland
Archive | 2009
Thilo Berkenbusch; Carl A. Busacca; Burkhard Jaeger; Richard J. Varsolona
Organic Process Research & Development | 2011
Jianxin Gu; Thomas Storz; Frederick Vyverberg; Charles Wu; Richard J. Varsolona; Karen Sutherland
Organic Process Research & Development | 2005
Rogelio P. Frutos; Magnus Eriksson; Xiao-Jun Wang; Denis Byrne; Richard J. Varsolona; Michael Dale Johnson; Lawrence Nummy; Dhileepkumar Krishnamurthy; Chris H. Senanayake