via a biaryl coupling using Heck reaction [273-275] has been developed by Harayama et al. [231,232]. The required 3-[2-bromoquinolin-3-yl]-4(3H)-quinazolinone 118 was prepared by N-alkylation of 2 with the quinolyl bromide 117, and the intramolecular biaryl coupling of 118 with the Pd reagent afforded 26 in good yields (Scheme 28). Synthesis of luotonin B 27 was fulfilled also by the NBS-mediated regioselective hydroxylation of 26 [231,232]. On the other hand, Mhaske and Argade fulfilled total synthesis of luotonins A (26), B (27), and E (29) by utilizing regioselective quinazolinone-directed ortho lithiation of quinazolinoylquinoline 119 as the key step (Scheme 28) [281]. The reaction of dilithiated intermediate 120 with formaldehyde yielded the desired 121 in high yield. The Mitsunobu cycli-zation [276] of 121 furnished 26 in 95% yield. The reaction of 120 with DMF furnished 27 via intermediate 122. The PCC oxidation of 121 fur-

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