five protected fragments ddz-phe-val-asn ( mbh ) -gln ( mbh ) -his ( dnp ) -leu-cys ( acm ) -gly-oh [ i ] , ddz-ser ( but ) -his ( dnp ) -leu-val-glu- ( obut ) -ala-oh [ ii ] , ddz-leu-tyr ( but ) -leu-val-cys ( mbzl ) -gly-oh [ iii ] , ddz-glu ( obut ) -arg ( tos ) -gly-oh [ iv ] , ddz-phe-phe-tyr ( but ) -thr ( but ) -pro-lys ( z ) -thr ( but ) -oh [ v ] for the synthesis of the human insulin b chain , were prepared by an efficient procedure on solid phase .
C0017797
gln
C0061472
glu