HCl in dichloromethane macrocycle treating with 2.1 molar equiv of HCl in CH2Cl2 at -78°C, warming slowly to 25°C, solvent removing; identified by NMR spectrum;

1: tetrahydrofuran 2: HCl / dichloromethane View Scheme

1: tetrahydrofuran 2: HCl / dichloromethane View Scheme

in tetrahydrofuran 0.03 M solns. of reagents adding over 2 h to THF at 25 degree.C; purified by preparative reverse phase chromy. and recrystn. from MeOH-THF, identified by X-ray crystallography, NMR spectra, and elem. anal.;