Design And Synthesis Of Novel Lipophilic Guanine Derivative

supramolecular self-assembly ubiquitous in nature. For example the double helixstructure of DNA is consisting of two complementary nucleotide chain following thepairing rules. Deoxynucleotide is the constituent units of DNA which base has its ownhydrogen bond donor and recipient sites, so between the bases and the base itself canself-assemble under supramolecular forces. Guanosine analogs, with their self-complementary hydrogen-bonding edges and aromatic surfaces, are programmed toself-associate. Guanine has two hydrogen bond acceptors (N7and O6) on its Hoogsteenface and two hydrogen bond donors (N1amide and N2amino) on its Watson–Crick face.Depending on the conditions, guanosine derivatives can selfassociate into dimers, ribbons,or macrocycles. These hydrogen-bonded structures can stack in solution due to theirpolarized aromatic surfaces. So G-quartet which is the constituent units ofself-association have used in liquid crystals, ion carrier, ion channel, nanometer devicesand bioscience field. Therefore synthesis nucleosides and their derivatives increasinglybecome a hot topic of supramolecular chemistry. lipophilic guanosine and its derivativesis the most widely used, which has become a kind of typical supramolecularself-assembly of monomers.For these reasons, we designed and synthesized two types of guanosine derivatives:(1) First, after a three-step reaction modify natural guanosine we obtained8-brominesubstitute lipophilic guanosine derivatives; then, after a two-step reaction we obtaineddifferent substituents4-phenyl-1-H-1,2,3-triazole; finally, under the catalysis of cuprouschloride, L-proline and K2CO38-bromine substitute lipophilic guanosine derivatives and4-phenyl-1-H-1,2,3-triazole react give the corresponding three8-triazole substitutedguanine derivative. (2) First, after a three-step reaction we obtained protected guanine to change itsfat-soluble; Second, after a four-step reaction we obtained6,7-dihydroxy-1-tetralone,using dimethyl-tert-butylchlorosilane, benzyl chloride and (3-bromopropoxy)-tert-butyldimethylsilane as protecting group give the corresponding hydroxy-protected ketone, theketone under Me-CBS or NaBH4reduction to give the corresponding alcohol; third,under the catalysis of diisopropyl azodicarboxylate alcohol react with the protectedguanine give the corresponding Mitsunobu product; finally, getting off the protectivegroup of guanine give two kind of9-non-glycosylated guanine derivatives.