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Keywords from Image Description:
Tetracycline ABCD.svg Allgemeine Struktur von Tetracyclinen Ringe beschriftet Generic structure of tetracycline antibiotics rings labelled own NEUROtiker Own work all rights released Public domain de einfach Ringe beschriftet Ringe beschriftet und nummeriertbr plain rings labelled rings labelled and numbered Tetracycline antibiotics