Photochemistry IV. A Photodeamination

Removal of drugs in aqueous systems by photoassisted degradation

“…Side-chain degradations by deamination, desulfuration and dealkylation are typical of many photolytic processes [19][20][21][22]. Photodeamination occurs when tetracycline is irradiated with UV light [11][12][13]. The removal of volatile dimethylamine, which requires the loss of only 2 atoms of carbon with respect to the 22 atoms of tetracycline, explains the small variation of the TOC values reported in Figure 4.…”

“…Absorption slowly decreases with irradiation time. The fall in the absorbance at 355 nm is accompanied by a very weak absorption in the visible region that can be attributed to the formation of 4a,12a-anhydro-4-oxo-4-dedimethylaminotetracycline [10,11]: Tetracycline photodecomposes easily and is converted to many decomposition compounds [11][12][13][14][15][16][17][18]. Side-chain degradations by deamination, desulfuration and dealkylation are typical of many photolytic processes [19][20][21][22].…”

Photoincorporation of tetracycline into Escherichia coli ribosomes

“…Taking note of the intrinsic photolability of tetracycline [3,4], we decided to investigate the possible photoincorporation of native [3H]TC into E. coli ribosomes. In this communication we: (i) Show that such incorporation takes place; (ii) Identify the major labeled ribosomal proteins as being S18 and S4, and to a lesser extent, S7, S13 and S14; (iii) Present evidence that the observed incorporation is related to the functional properties of TC.…”

Chemical Modification of the Tetracyclines

“…Deamination can also be achieved by photolysis of tetracycline (5) (HLAVKA and BITHA 1966). 4-Epitetracycline (34) undergoes no photoelimination und er these conditions.…”