neocarzinostatin chromophore [ NCS-Chrom,NCS-Chrom A,NCS-Chrom B,NCS-Chrom C,NCS-Chrom D ] nonprotein chromophore of neocarzinostatin; antibiotic activity of Neocarzinostatin depends on wholy on chromophore interaction with DNA; Chrom A & Chrom B are separated by HPLC; Chrom C is derived fr