EA-1699, also known as IIVX, is an extremely toxic synthetic chemical compound in the organophosphorus class, specifically, a thiophosphonate. It was derived from the more widely known nerve agent VX and can be seen as the dimethyl analogue of it.
Indicators of EA-1699 have been detected at a Syrian chemical weapons production facility.
Synthesis The synthesis of EA-1699 is analogous to that of VX with the N,N-diisopropylaminoethanol being replaced with N,N-dimethylaminoethanol.
The B in the following diagram denotes a base with diethylaniline being described as a suitable one in literature.
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