Flve 7-nltro-4-benzofurmzanyl ethers have been Synthesized and their water solubllitles and reactivities have been determlned. 4-Methoxy-7-nltrobenzofurazan (NBD-OCH,) has a solublllty slmllar to that of 4-chloro-7-nltrobenzofurazan (NBD-CI) but reacts-3.5 tlmes faster wlth hydroxyprollne. Hydroxyprollne reacts quantltatlvely wlth NBD-OCH, In acetonltrlle- water, while conslderable losses are seen when NBD-CI Is used In this; medlum. 4-(2- ...