HIROAKI SAWAI ET AL: "Synthesis and Reactions of Nucleoside 5'-Diphosphate Imidazolide. A Nonenzymatic Capping Agent for 5'-Monophosphorylated Oligoribonucleotides in Aqueous Solution", JOURNAL OF ORGANIC CHEMISTRY, vol. 64, no. 16, 1 August 1999 (1999-08-01), pages 5836 - 5840, XP055331109, ISSN: 0022-3263, DOI: 10.1021/jo990286u (B1)

I. I. KOUKHAREVA ET AL: "Chemical Route to the Capped RNAs", NUCLEOSIDES, NUCLEOTIDES AND NUCLEIC ACIDS., vol. 23, no. 10, 1 January 2004 (2004-01-01), US, pages 1667 - 1680, XP055553747, ISSN: 1525-7770, DOI: 10.1081/NCN-200031492 (B1)

M. ISHIKAWA ET AL: "Preparation of eukaryotic mRNA having differently methylated adenosine at the 5'-terminus and the effect of the methyl group in translation", NUCLEIC ACIDS SYMPOSIUM SERIES, vol. 53, no. 1, 1 September 2009 (2009-09-01), GB, pages 129 - 130, XP055331388, ISSN: 0261-3166, DOI: 10.1093/nass/nrp065 (B1)

Y. THILLIER ET AL: "Synthesis of 5' cap-0 and cap-1 RNAs using solid-phase chemistry coupled with enzymatic methylation by human (guanine-N7)-methyl transferase", RNA, vol. 18, no. 4, 14 February 2012 (2012-02-14), US, pages 856 - 868, XP055553150, ISSN: 1355-8382, DOI: 10.1261/rna.030932.111 (B1)

WO-A2-2008/016473 (B1)

WO-A2-2009/058911 (B1)

ROBERT E. SMITH ET AL: "A Unique Class of Compound, Guanosine-Nucleoside Tetraphosphate G(5')pppp(5')N, Synthesized during the in Vitro Transcription of Cytoplasmic Polyhedrosis Virus of Bombyx mori STRUCTURAL DETERMINATION AND MECHANISM OF FORMATION*", THE JOURNAL OF BIOLOGICAL CHEMISTRY, vol. 257, no. 1, 1 January 1982 (1982-01-01), pages 485 - 494, XP055331398 (B1)