mmino-3-((2S)-tetraidrofuran-2-il)-3,4-didehydrocepham-4-carbossilato di 4-nitrobenzile, cloridrato ###>itrobenzyl (7R)-7-amino-3-((2S)-tetrahydrofuran-2-yl)-3,4-didehydrocepham-4-carboxylate hydrochloride