2637254 EHNA erythro-9-(2-hydroxy-3-nonyl)adenine 236 2637255 EHNA erythro-9-(2-hydroxy-3-nonyl) adenine hydrochloride 20 2637258 EHNA erythro-3-(adenin-9-yl)-2-nonanol 1 2637257 EHNA erythro-6-amino-9(2-hydroxy-3-nonyl)-purine hydrochloride 1 2637256 EHNA erythro-9-(3-nonyl-p-aminobenzyl)adenine 1