Nonionic radiographic contrast agents

A method of diagnostic imaging of a mammalian host comprising the steps of:

• administering an effective amount of a contrast medium to the host, the contrast medium comprising a compound of the following formula:
• ##STR75## wherein Y is a single bond, --CH.sub.2 CH.sub.2 --, --CH.sub.2 O--, --OCH.sub.2 --, ##STR76## --CH.sub.2 --, --CH.sub.2 --CH.sub.2 --CH.sub.2 --, --O-- or ##STR77## R.sub.1, R.sub.1 ' and R.sub.2 are the same or different and are hydrogen, alkyl or hydroxyalkyl;
• R.sub.3 and R.sub.4 are the same or different and are hydrogen, alkyl or --CH.sub.2 CH.sub.2 OH;
• R.sub.5 is hydrogen, alkyl, --CH.sub.2 CH.sub.2 OH, CH.sub.2 OH or OH;
• R.sub.6 is alkyl, --CH.sub.2 CH.sub.2 OH, CH.sub.2 OH, OH or hydrogen and may be the same or different than R.sub.5 and m is zero or one, with the proviso that no methylene or methine carbon atom of the heterocyclic ring is attached to both a nitrogen and an oxygen atom and with the additional proviso that when Y is a single bond, m is not zero;
• and
• obtaining an image of all or part of the host.

A method of x-ray imaging of a mammalian host comprising the steps of:

• administering an effective amount of an x-ray contrast medium to the host, the x-ray contrast medium comprising a compound of the following formula:
• ##STR78## wherein Y is a single bond, --CH.sub.2 CH.sub.2 --, --CH.sub.2 O--, --OCH.sub.2 --, ##STR79## --CH.sub.2 --, --CH.sub.2 --CH.sub.2 --CH.sub.2 --, --O-- or ##STR80## R.sub.1, R.sub.1 ' and R.sub.2 are the same or different and are hydrogen, alkyl or hydroxyalkyl;
• R.sub.3 and R.sub.4 are the same or different and are hydrogen, alkyl or --CH.sub.2 CH.sub.2 OH;
• R.sub.5 is hydrogen, alkyl, --CH.sub.2 CH.sub.2 OH, CH.sub.2 OH or OH;
• R.sub.6 is alkyl, --CH.sub.2 CH.sub.2 OH, CH.sub.2 OH, OH or hydrogen and may be the same or different than R.sub.5 and m is zero or one, with the proviso that no methylene or methine carbon atom off the heterocyclic ring is attached to both a nitrogen and an oxygen atom and with the additional proviso that when Y is a single bond, m is not zero;
• and
• obtaining an x-ray image of all or part of the host.