合成路线1

The reaction of N-(tert-butoxycarbonyl [Boc])-4-O-methyl-L-tyrosine (I) with N,O-dimethylhydroxylamine (II) by means of dicyclohexylcarbodiimide (DCC) in THF gives the corresponding amide (III), which is reduced with LiAlH4 in ethyl ether yielding N-(tert-butoxycarbonyl)-4-O-methyl-L-tyrosinal (IV). The reductocondensation of (IV) with Nomega-tosyl-L-arginine (V) in methanol/acetic acid affords Nalpha-[2(S)-(tert-butoxycarbonylamino)-3-(4-methoxyphenyl)propyl]-Nomega-tosyl-L-arginine (VI), which is then attached to a polyestyrene resin (Merrifield resin) by means of DCC and dimethylaminopyridine (DMAP) to give the starting peptide-resin complex (IX). This resin (IX) is introduced into a Beckman 990 peptide synthesizer and submitted to successive amino acid coupling cycles (deprotection with TFA and coupling with (benzotriazol-1-yloxy)tris(dimethylamino)phosphonium hexafluorophosphate [BOP]) in order to introduce successively Boc-L-proline (X), Boc-L-serine (XII), Boc-L-(2-thienyl)alanine (XIV), Boc-glycine (XVI), Boc-L-(4-benzyloxy)proline (XVIII), Boc-L-proline (X), and Boc-L-(Nomega-tosyl)arginine (XXI) yielding resins (XI), (XIII), (XV), (XVII), (XIX), (XX), and the final resin (XXII), successively. The final peptide (RMP-7) is liberated from the resin (XXII) and simultaneously deprotected by a treatment with anhydrous HF with a 10% anisole and purified by HPLC over a C18 reverse phase column using trifluoroacetic acid/acetonitrile with a 0-25% gradient. Tritiated RMP-7 is obtained by bromination of RMP-7 with Br2 in acetic acid giving a monobrominated compound (XXIII) (basically the 5-position of the thiophene ring of thienylalanine is brominated), which is then tritiated with 3H2 and Pd/C in water.