630413-93-3Relevant academic research and scientific papers
New and practical method for synthesis of 1- and 1,3-substituted xanthines
Zavialov, Ilia A.,Dahanukar, Vilas H.,Nguyen, Hoa,Orr, Cecilia,Andrews, David R.
, p. 2237 - 2240 (2004)
A new and practical method for the synthesis of 1- and 1,3-substituted xanthines is reported. Direct base-promoted condensation of the imidazole precursor 1 with carbamates 2 gives 1-substituted 7-PMB xanthines 7 in good yields. Alkylation of these derivatives or their potassium salts proceeds under mild conditions to give functionalized 1,3-substituted 7-PMB xanthines 9 in good to excellent yields. The obtained 7-PMB-protected derivatives can be readily deprotected to give the parent 1- and 1,3-substituted xanthines.
Process for preparing xanthine phosphodiesterase V inhibitors and precursors thereof
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Page 11, (2008/06/13)
A process for preparing xanthine phosphodiesterase V inhibitors, and compounds utilized in said process. The process includes a five-step methodology for efficient synthesis of Compound 5 without intermediate purifications or separations, a dihalogenation step to synthesize Compound 7, and a coupling reaction to produce Compound 9.
