United States Patent Patent number: US9040490 B2 Application number: US 13/576709 Cytosine analogue, a method of preparation of a cytosine analogue, a DNA methyltransferase 1 inhibitor, a method for DNA methylation inhibition, the use of the analogue in the treatment of diseases associated with deviations from normal DNA methylation Inventors: J. Barciszewski, W.T. Markiewicz, E. Adamska, B. Plitta, M. Giel-Pietraszuk, E. Wyszko, M. Markiewicz, A. Fedoruk-Wyszomirska, T. Kulinski, M. Chmielewski Assignee: Institute of Bioorganic Chemistry, PAS, Poznań Date of Patent: 26. 05. 2015 European Patent Application PCT number: PCT/PL2011/000032 Cytosine analogue, a method of preparation of a cytosine analogue, a DNA methyltransferase 1 inhibitor, a method for DNA methylation inhibition, the use of the analogue in the treatment of diseases associated with deviations from normal DNA methylation Inventors: J. Barciszewski, W.T. Markiewicz, E. Adamska, B. Plitta, M. Giel-Pietraszuk, E. Wyszko, M. Markiewicz, A. Fedoruk-Wyszomirska, T. Kulinski, M. Chmielewski Assignee: Institute of Bioorganic Chemistry, PAS, Poznań Application Date: 17. 03. 2011 Polish Patent Application Polish Application number: P 390 769 Cytosine analogue, a method of preparation of a cytosine analogue, a DNA methyltransferase 1 inhibitor, a method for DNA methylation inhibition, the use of the analogue in the treatment of diseases associated with deviations from normal DNA methylation Inventors: J. Barciszewski, W.T. Markiewicz, E. Adamska, B. Plitta, M. Giel-Pietraszuk, E. Wyszko, M. Markiewicz, A. Fedoruk-Wyszomirska, T. Kulinski, M. Chmielewski Assignee: Institute of Bioorganic Chemistry, PAS, Poznań Application Data: 19. 03. 2010 Published also as: EP2556081A2, US20120322755, WO2011115513A2, WO2011115513A3, WO2011115513A9 Abstract In this study, a cytosine analog and its preparation method and a DNA methyltransferase 1 inhibitor and a method for DNA methylation inhibition are provided for the treatment of diseases associated with deviations from normal DNA methylation. The analog of cytosine comprises of 1, N4, 5, and 6-substituted derivatives of cytosine or 5,6-dihydrocytosine; the analog can be described with a chemical formula where R1 is H, R3, R4, 2-deoxyribosyl, R4 is alkyl or aryl, X is N or C – if X in formula I is N, then R5 is no substituent and if X in formula I and/or II is C or if X in formula II is N, then R5 and R6 are independently alkyl, aryl, hydroxyalkyl, aminoalkyl, hydroxyl, carboxyl, amino group, alkoxyl, aryloxyl, aminoalkyl, aminoaryl, thio group, sulfonyl, sulfinyl, or halogen.