1-Hydroxybenzotriazole → HCID 178454183, compound

Participants

Reaction Steps

To a stirred solution of Boc-L-Arg-L-Trp-OH hydrochloride (100 mg, 0.20 mmoles), H-D-Arg-D-Trp-OBzl di-p-toluenesulphonic acid (175 mg, 0.21 mmoles), HOBt (110 mg, 0.72 mmoles) and DIPEA (164 μl, 0.96 mmoles) in DMF (2 ml) cooled on ice was added HBTU (91 mg, 0.24 mmoles) in small portions over 10 minutes. The mixture was stirred on ice for 3 hours and workup performed as described for KP-3-2. After workup, the organic layer contained only minor amounts of the desired product as judged by analytical RP-HPLC. The pooled water phases was extracted with 3×15 ml ethyl acetete and evaporated to afford the crude product.

Provenance & Evidence