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A novel and efficient synthesis of N-aryl and N-heteroaryl sulfamides via an intermolecular palladium-catalyzed coupling process has been developed. The reactions proceeded with good to excellent yields and were tolerant of a wide range of functional groups. [reaction: see text]

A concise total synthesis of the thiazoline-thiazole containing metabolite didehydromirabazole A 1 is described. The synthesis uses the unusual amino acid (R)-2-rnethylcysteine 20 in sequential cyclocondensations with imino ethers as key steps, viz 22 -, 32 and 37 + 38. Didehydromirabazole A 1 is a member of a unique family of cytotoxic alkaloids, known as 'mirabazoles' and 'tantazoles', which have recently been isolated from the terrestrial bluegreen alga Scytonemu mirabile. ',' Other members include tantazole A 2, mirabazole C 3 and tantazole 14, and they all show structures which are based on the linear fusion of four or five successive 2,4-disubstituted thiazoline/thiazole/oxazole rings terminating in a 2 isopropyl thiazo1ine.t The extensive studies of Moore et al. have shown the presence of three other classes of cytotoxins in S. mirabile, uiz scyt~phycins,~ mirabimides and mirabilene is on it rile^.^ Several of these compounds, including the tantazoles and mirabazoles show pronounced solid tumour selective toxicity.