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Some spiro[indoline-naphthoxazines] I and spiro[indoline-pyridobenzoxazines] I1substituted by different groups were synthesized in order to evaluate their photochromic properties 1 and to optimize the preparation of spiroheterocyclic systems. In addition, some spiro[indoline-naphthopyrans] 111 were also pre ared as reference compounds. Their physical and spectroscopic characteristics (UV, 'H and ' C NMR) were determined. A study using the experimental design methodology allowed to point out the most important factors for improving the reaction yields. B INTRODUCTIONLes composds spiranniques constituent une classe importante parmi les photochromes organiques. Ces photochromes peuvent &tre ddfinis comme des colorants rdversibles sous induction photochimique, gdndralement UV. L'absorption photonique UV par le composd spirannique (forme fermk) (Schdma l), conduit B la formation d'dtats excit6s2$3 et A la rupture de la liaison carbone spirannique-oxygbne, puis A I'isomdrisation en photomdrocyanine transoyde quasi-plane, forme ouverte absorbant dans le visible.

We used an experimental design (Scheffe simplex-centroid design) to examine ingredient interactions in food protein mixtures and their effects on functional properties. A defined and limited number of milk, albumen, and egg yolk blends were made and evaluated for heat gelation properties and for emulsifying and foaming capacity and stability. The method accounted for nonlinear interactions between the ingredients. Synergistic effects were revealed on heat gelation and emulsifying properties but antagonistic effects for foaming properties were noted.

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