OROTIC ACID AND ITS ANALOGUES: PART II. ON THE ALKALINE REARRANGEMENT OF 5-CARBOXYMETHYLIDENEHYDANTOIN

The in vitro conversion of 5-carboxymethylidenehydantoin to orotic acid is not likely to occur in vivo since the two substances have antagonistic effects (2). A sulphur analogue of the above hydantoin has been prepared and shown not to undergo alkaline rearrangement to the corresponding metathiazine structure. The mechanism of orotic acid formation is discussed.