beta-D-GlcpA-(1->4)-alpha-D-GlcpNAc6S-(1->4)-[4)-beta-D-GlcpA-(1->4)-alpha-D-GlcpNAc6S-(1->]-[4)-alpha-L-IdopA2S-(1->4)-alpha-D-GlcpN2,6S2-(1->]-alpha-L-IdopA2S-(1->4)-D-GlcN2,6S2(?->