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Recent reports from these laboratories described new synthetic technologies and strategies for the construction of the ABCD"] and E[' I ring systems of brevetoxin A (l).[31 In this communication we describe an efficient and stereocontrolled synthesis of the FGHIJ ring framework (2) of this novel neurotoxin.An attractive retrosynthetic analysis of brevetoxin A (1) with a high degree of convergency is shown in Scheme 1. Thus initial disconnection of the indicated strategic bonds of 1 (dotted lines) leads to the appropriately functionalized intermediate 2 containing the FGHIJ ring framework of the target molecule. Further disconnection of the G ring of the newly generated intermediate 2 as shown leads to compounds 3 and 4 as potential precursors. In order to ensure a high yielding formation of the 8-membered ring system in 3, an additional ring was temporarily installed in its pregenitor (5) (to decrease number of rotations and facilitate ring closure). Finally, disconnection of 6,7, and 4 led to enantiomerically pure precursors of the correct stereogenicity, namely 2-deoxy-~-ribose, tri-0-acetyl-D-glucal, and D-mannose, respectively. The successful execution of the designed strategy for reaching 2 is described below.Syntheses of key intermediates 6 and 7 are briefly summarized in Scheme 2. Thus, 2-deoxy-~-ribose was converted into olefin 9 (65 % overall yield) by a Wittig reaction followed by sequential and selective protection involving 1,3-benzylidene formation and silylation. Subsequent ozonolysis-reduction led to alcohol 10, which was then converted into phosphonium salt 6 via iodide 11 by standard chemistry (68 % overall yield). For the synthesis of 7, tri-0-acetyl-D-glucal (Scheme 2) was converted into 12 by methods previously described from these laboratoriesc41 followed by selective monosilylation. Epoxidation with mCPBA gave the a-epoxide 13 as a single product (75 %), which was transformed into epoxyketone 14 by PDC treatment (86%