Trachoma viruses

Amino- and hydrazino-quinazolines exhibited antibacterial ac-tivity and a patent claim on the in vitro action of 2,4-diamino-quinazolines was rnade. The preparation of thiopegan derivatives as potential antimalarials and antibacterials deserves mention. Complete inhibition of influenza virus in vitro but not in vivo was shown by. 6,8-dichloro-2,4-dihydroxyquinazoline and other cyclic ureas. Activity against trachoma virus was also displayed by several 2-trichloromethylquinazolines. ... 

The infectious elementary bodies of trachoma agent belong to the Chlamydiae which are parasites of mammalian cells and are considered unusually small bacterial cells. As in the case of vaccinia virus, only certain ansamycins, e.g. rifampicin at very high concentrations, affect the growth of trachoma agent. The mechanism of action is not known, but again RNA synthesis is not involved. 

Hurst, E. W. and Hull, R. I. 1961. Two new synthetic substances active against viruses of the psittacosis-lymphogranuloma-trachoma group. J. Med. Pharm. Chem. 3 215-229. 

Only rifampicin can prevent the development of pox viruses at concentrations completely harmless for the host cell The mechanism of action of rifampicin on these large DNA viruses is now being studied and appears different from that on bacterial cells. This is an approach to specific antiviral chemotherapy and by now the rifampicin has been shown to exert its selective activity on some large DNA viruses (pox viruses and adenoviruses type I) and on the trachoma agent However, the rifampicin activity is limited it does not prevent the replication in mammalian cells of small DNA viruses nor the RNA viruses. 

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