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Carbohydrates, inexpensive chiral sources, are very useful for many syntheses of chiral bioactive compounds. We have chosen to synthesize benzyl α- d -mannofuranosides and d -lyxofuranosides with dioxolane-type, 2,3-O-isopentylidene and 2,3-O-benzylidene acetals from d -mannose. Interestingly, we have discovered new knowledge about the cleavage of dioxolane-type using two catalysts, Cu(OTf)2/BH3·THF and TiCl4/Et3SiH. The results showed that the regioselectivity of the benzylidene acetal ring opening was affected by the adjacent hydroxy (OH) group and was not directed by the stereochemistry of the acetal center. The substrates containing OH groups at position 5 can be cleaved by Cu(OTf)2/BH3·THF in tetrahydrofuran to exclusively provide the 2-O-benzyl-3-hydroxy compounds. When the substrates bore the OH group at position 6, using TiCl4/Et3SiH in dichloromethane gave a similar pattern. If the substrates lacked the OH group at position 5 or 6, the reactions did not proceed or gave low selectivity. Our discovery is very useful for dioxolane-type ring opening of carbohydrate synthesis.

The described transformation tolerates a broad variety of functional groups and uses ammonium tartrate as a novel ammonia surrogate.

Starting from 1-hydroxy-2-naphthoic acid, a series of novel naphthoquinone aromatic amides is synthesized by a new route using Fremy′s salt oxidation and tBu-OOH/TritanB hydroxylation as the key steps.

Clausena excavata Burm. f. (Rutaceae) is a medicinal plant which is used in folklore medicine for treatment of cold, malaria, AIDS, dermatopathy, abdominal pain, and snake-bite. This plant is a rich source of coumarins and carbazole alkaloids. So far, fifty-three coumarins and fifty-eight carbazole alokaloids were isolated from C. excavata. Furthermore, a small group of tetranortriterpenoids, steroids, flavonoids, and essential oils were also obtained from this plant. C. excavata showed diverse therapeutic activities which are antibacterial, antifungal, antiplatelet, antiplasmodial, antitumor, antinociceptive, immunomodulatory, antimycobacterial, and anti-HIV-1 activities. The incidence of HIV-1 infection leading to AIDS has increased every year, and fungal and bacterial infections, particularly TB-causing mycobacteria are prevalent in HIV-infected patients. So Clausena excavata which showed inhibition of these diseases, is very promising to be developed for treatment of AIDS.

Total synthesis of isagarin (2) has been accomplished in five steps with 24.1% overall yield from 2‐bromonaphthoquinone (6). The key step is a palladium‐catalyzed cyclization to form a bicyclic ketal ring.

A cholesterol model compound, containing 16β‐acetoxy, 17α‐hydroxy, and (20S, 22R)‐epoxy groups was synthesized from diosgenin in 13 steps and was rearranged regio‐ and stereo‐specifically to an orthoester with BF3·Et2O.

The first syntheses of 16β-chloro- and 16β-bromo-cyproterone acetate is described. The preparation of 16β-chlorocyproterone acetate was accomplished in eight steps (6.5% overall yield) from commercially available 16-dehydropregnenolone acetate. 16β-Bromocyproterone acetate was prepared from 16β-chlorocyproterone acetate with base-induced epoxide formation as the key step.

(±)-Frontalin was synthesized in a few steps sequence starting from ethyl acetoacetate involving intramolecular cyclization using palladium chloride as catalyst.