P-Cresol → HCID 178461612, compound

Participants

Reaction Steps

The crude cyclo(-pClPhe-D-Arg(Tos)-Phe-D-Ala-Trp-) (100 mg) as obtained in Example 38 was treated with HF in the presence of p-cresol (100 mg) and ethanedithiol (100 ml) for 2 hours, while cooling with ice. After HF was removed by distillation, ether was added to the residue and the precipitate formed was collected by filtration. This was purified by gel chromatography (G-25; 2 cm×80 cm). Finally, 1/5 of the product was further purified by HPLC using a column for partitioning purification of D-ODS-5-ST (2 cm×15 cm; produced by YMC Co.) to obtain cyclo(-pClPhe-D-Arg-Phe-D-Ala-Trp-).

Provenance & Evidence