4-Nitrophenyl 2-O-alpha-D-glucopyranosyl-alpha-D-mannopyranoside 79580-51-1 NGPMP Para-nitrophenyl 2-O-alpha-D-glucopyranosyl-alpha-D-mannopyranoside alpha-D-Mannopyranoside, 4-nitrophenyl 2-O-alpha-D-glucopyranosyl-