The present invention relates to novel compounds of the naphthopyran type which have an annelated carbocycle in position 5,6. These compounds are of formula (I) given below: ##STR00001## in which A is an alicyclic ring which is optionally annelated with an aromatic ring and in which two adjacent R.sub.3 can together form at least one ring, for example a benzo group. These compounds (I) possess interesting photochromic properties. The invention also relates to the method of preparing these compounds (I), as well as their applications as photochromes and compositions and (co)polymer matrices comprising them.

 
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