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BocHNSEMOBO OONH5bOHNISEMOORink-MBHABocHNIBocHNOOMeOSEMN N OBrBocHNOMeOMe1) Pd 2 (dba) 3 , P(o-tolyl), ArXKF, DME/EtOH/H 2 OMW, 120 ºC, 30 min2) LiOH, THF, rt, 24 h3) TFA/TIS/H 2 O, rt, 2 hScheme 4. Suzuki-Miyaura arylation of Boc-Tyr(3-BPin,OSEM)-Leu-Leu-Rink-MBHA (5b).Table 1. Arylation of resins 3 and 5b under microwave irradiationArX Peptide Peptide purity (%) a 8 (%) a7a 91 89a 55 167b 57 129b 45 187c 40 89c 18 60a Percentage determined by HPLC at 220 nm from the crude reaction mixtureHOH 2 NArONH9a-cOHNOHNH 2 N2+HOONH8OHNONH 2Linear precursors containing the corresponding amino acid boronate and the haloarylresidue were prepared using the Miyaura conditions previously optimized. Then,cyclization via a Suzuki-Miyaura cross-coupling was performed under microwaveirradiation. After cleavage, biaryl peptides 10-15 were obtained in moderate to goodpurities.H 2 NH 2 NO HNHNOH 2 NOHNONHHNOONHNH 2OH 2 NH 2 NHNOH 2 NO HNNH 210 (75% Purity) 11 R=Me (71% Purity)OR 12 R=H (78% Purity)OHNONHOHNONHOH 2 NH 2 NO HNHNOH 2 NOHNONH NH 2O13 (75% Purity)H 2 NH 2NHNOHNOH 2 NOHNONHNH 2OOR14 R=Me (75% Purity)15 R=H (76% Purity)The above methodology was extended to the synthesis of biaryl cyclic peptides of differentsizes. Biaryl peptides were obtained in purities ranging from 35 to 67%.AcknowledgmentsAna Afonso is recipient of a predoctoral fellowship from the MICINN of Spain. This work wassupported by grants AGL2006-13564-C02-02/AGR and AGL2009-13255-C02-02/AGR (MICINN ofSpain).References1. Feliu, L., Planas, M. Int. J. Pept. Res. Ther. 11, 53-97 (2005).2. Afonso, A., Rosés, C., Planas, M., Feliu, L. Eur. J. Org. Chem. 1461-1468 (2010).3. Miyaura, N., Suzuki, A. Chem. Rev. 95, 2457-2483 (1995).45