合成路线1

The hydrolysis of the chiral unsaturated bicyclic lactam (I) with aqueous refluxing HCl gives the amino acid (II), which is esterified with 2,2-dimethoxypropane, methanol and HCl to yield the methyl ester (III). The acylation of (III) with Ac2O and pyridine in dichloromethane affords the acetamide (IV), which is reduced with calcium borohydride in THF, providing the carbinol (V). The hydrolysis of the amido group of (V) with HCl in refluxing ethanol/water gives the chiral amino alcohol (VI), which is condensed with 2-amino-4,6-dichloropyrimidine (VII) by means of DIEA in refluxing butanol, yielding the adduct (VIII). The reaction of (VIII) with 4-chlorophenyldiazonium chloride (IX) by means of HOAc and NaOAc in water affords the azo compound (X), which is reduced with Zn and HOAc to provide the triaminopyrimidine (XI). The cyclization of (XI) with triethyl orthoformate gives the carbocyclic chloropurine (XII), which is finally treated with NaOH in refluxing water to yield the target carbocyclic guanine.