GC Conditions: Column: DB-1(100% -polydimethylsiloxane), Length: 30m; I. D: 0.25 mm; Film: 1.0 µm; Injection temp.: 250 °C; Detector (FID) temp.: 275 °C; Column Temp.: 80 °C initial, programmed at 10 °C/ min. to 250 °C; Hold for 15 min. Sample: 0.2 µl in DMF.