XANTHENE DERIVATIVES

摘要

Secondary amide xanthene derivatives, termed "xanthamides", and other xanthene derivatives, are obtained in one form as fluorescent dyes which can have much higher photostability than related dyes such as fluorescein and BODIPY-FL. Examples are presented in which the synthesis begins with 5-carboxyfluorescein, an inexpensive reagent. Related carboxyxanthenes employed in other dyes such as rhodamines can also be used as starting materials. Simple synthetic steps yield compounds which exemplify this invention. Other notable properties of the xanthamide dyes include the option of pH-independent fluorescence, and the ease of controlling their functional and other groups. This means that a diversity of xanthamide and related xanthene dyes can be prepared with a broad variation of physicochemical properties to enhance the usefulness of fluorescence in biological and chemical analysis, and in other areas. In a second form xanthamides are formed which can be used as precursors of xanthamide dyes, especially as indicators or quenchers of reactive oxygen or free radical species.