Mirabazole 8 (3) has been prepared in &even atepa from a-~t~~~e~.The mirabaroles (l-4) are a group of thiazolineAhiazole-containing marine alkaloids isolated from the blue-green alga Scytonema Mirabile.~ These natural products and the structuralty similar tantazoleS2 and thiangazoles have raixntfy stirmfated ConSiderable synthetic interest4E@*7 because of their unique structures and biobgiil activity. We have previously developed a strategy for synthesis of mirabazoles in which the four heterocyclic rings are simultaneously formed by TiCl~madiited cyckdehydration of an appropriate tripeptide diamide. This procedure was applied for a synthesis of the StNCtUri3 originalfy assigned to mirabazole Cs and for a syntheaii of the newly-assigned structure.* In this appmach, qckatbn to form the three substituted thiazoline rings proceeds eaaify, but the terminal ~~~~~ ring is fcinned more slowly and requires repeated submission to the cyciiiatbn condiins. The oxidative instability of the free thiifs makes fTUnipU&tbn of the partially cycfiied material diikulf and in most cases leSdS to Complicated reaction mixtures and bw product yields. To avoid this cyclization difficulty, we have made a sligM modiiibn of our synthetk etrategy, such that only the substituted thiazoline rings are formed'in the TiCl,t-mediated cyckdehydratffn step. In this Letter, we report a total synthesis of mirabazole B (3) using this modified strategy.