We determined the nucleotide sequences of an 896-base pair region of mitochondrial DNA (mtDNA) from 20 primates representing 13 species of macaques, a baboon, and a patas. We compared these sequences and the homologous sequences from four macaques and a human against each other and deduced the phylogenetic relationships of macaques. The results from the phylogenetic analyses revealed five groups among the macaques: (1) Barbary macaque, (2) two species of Sulawesi macaques, (3) Japanese, rhesus, Taiwanese, crab-eating, and stump-tailed macaques, (4) toque, pig-tailed, and lion-tailed macaques, and (5) Assamese and bonnet macaques. The phylogenetic position of Tibetan macaque remains ambiguous as to whether it belongs to the fourth or fifth group. Phylogenetic trees revealed that Barbary macaque diverged first from the other Asian macaques. Subsequently, the four groups of Asian macaques diverged from one another in a relatively short period of time. Within each group, most of the species diverged in a relatively short period of time following the divergence of the groups. Assuming that the Asian macaques diverged from the outgroup Barbary macaque three million years ago (MYA), the divergence times among groups of Asian macaques were estimated at 2.1-2.5 MYA and within groups at 1.4-2.2 MYA. The intraspecific nucleotide diversity observed among three rhesus macaques was so large that they did not form a monophyletic cluster in the phylogenetic trees. Instead, one of them formed a cluster with Japanese and Taiwanese macaques, whereas the other two formed a separate cluster. This implies that either polymorphisms of mtDNA sequences that existed before the divergence of these three species (ca. 700,000 years ago) have been retained in rhesus macaques or introgression has occurred among the three species.

A general and mild catalytic allylation of carbonyl compounds, applicable to aldehydes, ketones, and imines is developed using allyltrimethoxysilane as the allylating reagent. The reaction proceeds smoothly with 1-10 mol % of CuCl and TBAT in THF at ambient temperature. Mechanism studies indicated that the copper alkoxide, allylfluorodimethoxysilane, and allyltrimethoxysilane are essential to promote the reaction efficiently. Preliminary extension of the reaction to the first catalytic enantioselective allylation of ketones using an allylsilane produced the product with 61% ee from acetophenone, using a CuCl-p-tol-BINAP-TBAT catalyst (15 mol %).

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The common synthetic intermediate of a potent and promising anticancer agent, fostriecin, was synthesized using a unique method that combines four catalytic asymmetric reactions as shown above.

Catalytic asymmetric synthesis of the natural antibiotic fostriecin (CI-920) and its analogue 8-epi-fostriecin and evaluation of their biological activity are described. We used four catalytic asymmetric reactions to construct all of the chiral centers of fostriecin and 8-epi-fostriecin; cyanosilylation of a ketone, Yamamoto allylation, direct aldol reaction, and Noyori reduction, two of which were developed by our group. Catalytic enantioselective cyanosilylation of ketone 13 produced the chiral tetrasubstituted carbon at C-8. Both enantiomers of the product cyanohydrin were obtained with high enantioselectivity by switching the center metal of the catalyst from titanium to gadolinium. Yamamoto allylation constructed the C-5 chiral carbon in the alpha,beta-unsaturated lactone moiety. A direct catalytic asymmetric aldol reaction of an alkynyl ketone using LLB catalyst constructed the chirality at C-9 with the introduction of a synthetically versatile alkyne moiety, which was later converted to cis-vinyl iodide, the substrate for the subsequent Stille coupling for the triene synthesis. Noyori reduction produced the secondary alcohol at C-11 from the acetylene ketone 6 with excellent selectivity. Importantly, all the stereocenters were constructed under catalyst control in this synthesis. This strategy should be useful for rapid synthesis of stereoisomers of fostriecin.

The novel tandem radical addition-cyclization of oxime ethers and hydrazones intramolecularly connected with the alpha,beta-unsaturated carbonyl group is described. The radical reaction of oxime ethers 1, 2, and 4 connected with acryloyl and methacryloyl moieties proceeded smoothly to give the heterocycles via a tandem C-C bond-forming process. The tandem reaction of hydrazone 5 took place in the presence of Zn(OTf)(2) as a Lewis acid to give the trans-cyclic product 17 without the formation of the cis-isomer. The diastereoselective radical addition-cyclization reaction of chiral oxime ether 19 was also studied. The tandem reaction of 19 proceeded smoothly even in aqueous media, providing the novel method for asymmetric synthesis of gamma-butyrolactones and beta-amino acid derivatives.

The radical addition-cyclization reaction of substrates having two different radical acceptors such as acrylate and aldoxime ether moieties was studied. This new free radical-mediated Mannich-type reaction proceeded smoothly via a tandem C-C bond-forming process. Furthermore, the diastereoselective tandem reaction provides the novel method for asymmetric synthesis of gamma-butyrolactones and beta-amino acid derivatives.

Melamine has recently been recognized as a food contaminant with adverse human health effects. Melamine contamination in some crops arises from soil and water pollution from various causes. To remove melamine from the polluted environment, a novel bacterium, Nocardioides sp. strain ATD6, capable of degrading melamine was enriched and isolated from a paddy soil sample. The enrichment culture was performed by the soil-charcoal perfusion method in the presence of triazine-degrading bacteria previously obtained. Strain ATD6 degraded melamine and accumulated cyanuric acid and ammonium, via the intermediates ammeline and ammelide. No gene known to encode for triazine-degrading enzymes was detected in strain ATD6. A mixed culture of strain ATD6 and a simazine-degrading Methyloversatilis sp. strain CDB21 completely degraded melamine, but the degradation rate of cyanuric acid was slow. The degradation of melamine and its catabolites by the mixed culture was greatly enhanced by including Bradyrhizobium japonicum strain CSB1 in the inoculum and adding ethanol to the culture medium. The melamine-degrading consortium consisting of strains ATD6, CDB21, and CSB1 appears to be potentially safer than other known melamine-degrading bacteria for the bioremediation of farmland and other contaminated sites, as no known pathogens were included in the consortium.