Tyropanoate Tyropanoic acid

Methohexital sodium Butyramidophenol Acebutolol Butyric anhydride lopanoic acid Tyropanoate sodium n-Butyryl chloride Ethacrynic acid... 

In contrast to the 2,4,6-triiodobenzoic acids, substituted alkanoic and alkoxyalkanoic acids containing a 2,4,6-triiodophenyl or a 2,4,6-triiodophenoxy group with open position 5, such as iopanoic acid, tyropanoate, iogly-camic acid, and iopronic acid, have both lipophilic and hydrophilic properties. These contrast acids have an acidity constant about two units higher than that of the water-soluble, fully substituted 2,4,6-triiodobenzoic acids (263) and are not completely ionized at the physiological pH. In the nonionized form, the contrast molecules can be absorbed and transported across cell membranes after oral administration. 

Ipodate, introduced in 1961, can yield visualization of both gall bladder and bile ducts. Tyropanoate, iopanoic acid, and ipodate are widely used in oral cholecystography. They show about the same efficacy but differ in the intensity of opacification,the frequency of dim and absent shadows, and the frequency of side effects. Russell and Frederick (867) compared these three agents but failed to demonstrate the superiority of any one of them. locetamic acid was favorably compared with and preferred to the above three agents, but skin reactions were reported in a few cases (775,868, 869). 

Russell, J. G. and Frederick, P. R. (1974) Clinical comparison of tyropanoate sodium, ipodate sodium and iopanoic acid. Radiology, 112, 519. 

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