This paper presents the results of an experiment, using white rats on a maze, which began as a study in orientation. We wished to offer the rat a choice between two pathways of equal length leading to the same food box, one starting toward the food box and the other starting in the opposite direction. By presenting this choice, we sought to find whether the rat would prefer the path whose initial section lay in the goal direction. The floor plan of the maze devised for this purpose is shown in figure 1. Under our first conditions, the rat showed clearly this preference. We then changed the experimental conditions somewhat "just to see what would happen" and obtained data which were unforeseen and surprising. The general nature of the results is that the preference of the rat for a specific pathway, at least in the present set up, is highly dependent upon the length of the daily trial series. Furthermore, when given 2 trials in close succession, the rats alternate between the two pathways almost perfectly. In other situations alternation is weak or absent. The twenty-four hour interval between trial series was the only one which was used.
The synthesis of a number of 8‐(dialkylamino)‐ and 8‐alkoxyxanthines (3 and 6, respectively) is described. Treatment of 3 with m‐chloroperoxybenzoic acid (m‐CPBA) gave by a novel rearrangement 3‐(disubstituted amino)‐4,7,9‐trimethyl‐1‐oxo‐2,4,7,9‐tetraazaspiro[4,5]dec‐2‐ene‐6,8,10‐triones 10. Also, the corresponding 3‐alkoxy‐subtituted spiro compounds 12 were obtained by an analogus treatment of 8‐alkoxyxanthines 6. In attempts to elucidate a tentative mechanism for this rearrangement 8‐[(dialkylamino)methyl]caffeines 7 when treated with m‐CPBA did not undergo the rearrangement but only yielded the expected N‐oxide derivatives 16. This result seems to indicate that a necessary structure element for this rearrangement to occur is an atom with an unshared pair of electrons to be attached to the 8‐position of the investigated xanthines. In agreement with this statement is the fact that N‐oxides of 8‐[(dialkylamino)methyl]caffeines 16 do not undergo the novel rearrangement but rather give the expected Meisenheimer rearrangement or the Cope elimination depending upon reaction conditions.
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