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Total synthesis of (-)-daphenylline, a hexacyclic Daphniphyllum alkaloid, was achieved. Construction of the tricyclic DEF ring system was initiated by asymmetric Negishi coupling followed by an intramolecular Friedel-Crafts reaction. Installation of a side chain onto the tricyclic core was carried out through Sonogashira coupling, stereocontrolled Claisen rearrangement by taking advantage of the characteristic conformation of the tricyclic DEF core, and the stereoselective alkylation of a lactone. After the introduction of a glycine unit, the ABC ring system was stereoselectively constructed through intramolecular cycloaddition of the cyclic azomethine ylide.

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Objective. We examined the reduction of T cell receptor (TCR) AV24؉,BV11؉ CD4؊,CD8؊ (doublenegative [DN]) natural killer T (NKT) cells in peri-NKT cells were present in healthy subjects and BD patients, respectively (P < 0.01). Three of 10 RA patients, 5 of 10 SLE patients, 4 of 8 SSc patients, and 6 of 9 SS patients (a total of 18 of 37 patients, or 48.6%) responded to ␣-GalCer, indicating that patients could be divided into two groups: ␣-GalCer responders and nonresponders. In contrast, NKT cells from all healthy subjects proliferated against ␣-GalCer. APCs from all nonresponder patients were found to function as ␣-GalCer-presenting cells, while NKT cells from nonresponders did not expand even in the presence of APCs from normal responders.Conclusion. These findings strongly suggest that patients with autoimmune diseases can be divided into two groups (␣-GalCer responders and nonresponders). They also suggest that the reduced numbers of NKT cells in patients with autoimmune diseases may be due to an inadequate amount of ␣-GalCer-like natural ligands (i.e., adequate in only 48.6% of patients) for the induction of NKT cells in vivo, or to a dysfunction in the NKT cells themselves (in 51.4% of patients).

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A total synthesis of (-)-histrionicotoxin was achieved. Our synthesis features preparation of a pseudosymmetrical dienyne through chirality transfer from an allenylsilane, a dienyne metathesis to produce the bicyclo [5.4.0] system in optically active form, selective functionalization of a diene via a 5-exo-trig iodoetherification, and an asymmetric propargylation.