Hiromasa Kiyota

Chemical and Pharmacological Research of the Plants in Genus Euphorbia

3.1. Biosynthesis from Jatrophanes 4313 3.2. Biosynthesis from Lathyranes 4314 4. Biological Activity 4314 4.1. Antiproliferative Activity 4314 4.2. Cytotoxicity 4316 4.3. Effects on the Cell Division 4316 4.4. DNA-Damaging Activity 4316 4.5. Modulatority of Multidrug Resistance 4316 4.6. Tumor Promoting Activity 4318 4.7. Pro-Inflammatory Activity 4318 4.8. Inhibition of Allergic Reactions 4318 4.9. Antimicrobial Activity 4319 4.10. Antidiarrheal Activity 4322 4.11. Antipyretic-Analgesic Activity 4322 4.12. Molluscicidal and Antifeedant Activities 4323 4.13. Inhibitory Activity on the Mammalian Mitochondrial Respiratory Chain 4323

Constituents from Salvia Species and Their Biological Activities

Yi-Bing Wu,† Zhi-Yu Ni,† Qing-Wen Shi,*,† Mei Dong,‡ Hiromasa Kiyota,* Yu-Cheng Gu,†,∥ and Bin Cong*,‡ †School of Pharmaceutical Sciences, Hebei Key Laboratory of Forensic Medicine, Hebei Medical University, Shijiazhuang, Hebei Province 050017, China ‡Department of Forensic Medicine, Hebei Medical University, Hebei Key Laboratory of Forensic Medicine, Shijiazhuang, Hebei Province 050017, China Department of Bioscience and Biotechnology for Future Bioindustry, Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiya, Aoba-ku, Sendai 981-8555, Japan Syngenta Jealott’s Hill International Research Centre, Berkshire RG42 6EY, United Kingdom

Natural Taxanes: Developments Since 1828

Natural Taxanes: Developments Since 1828 Yu-Fang Wang, Qing-Wen Shi,* Mei Dong, Hiromasa Kiyota,* Yu-Cheng Gu, and Bin Cong* School of Pharmaceutical Sciences, Hebei Medical University, Shijiazhuang, Hebei Province, 050017, China Department of Forensic Medicine, Hebei Medical University, Hebei Key Laboratory of Forensic Medicine, Shijiazhuang, Hebei Province, 050017, China Department of Bioscience and Biotechnology for Future Bioindustry, Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiya, Aoba-ku, Sendai 981-8555, Japan Syngenta Jealott’s Hill International Research Centre, Berkshire, RG42 6EY, U.K.

Biosynthesis and metabolism of abscisic acid and related compounds

This review describes research on the chemistry (biosynthesis, metabolism and synthetic analogs) of a plant hormone, abscisic acid (ABA), covering 1970 to 2002 with 123 references

Induction of differentiation of human myeloid leukemia cells by jasmonates, plant hormones

Some regulators of plant growth and differentiation have been shown to induce the differentiation of several human myeloid leukemia cells, and might be effective as differentiation inducers to control acute myelogenous leukemia cells. In this study, the growth-inhibiting and differentiation-inducing effects of jasmonates on human myeloid leukemia cells were examined. Several myeloid leukemia cells were cultured with methyl jasmonate (MJ) and its derivatives. Cell differentiation was determined by nitroblue tetrazolium-reducing activity, morphological changes, α-naphthyl acetate esterase activity and expression of differentiation-associated surface antigens. MJ induced both monocytic and granulocytic differentiation of HL-60 cells. MJ activated mitogen-activated protein kinase (MAPK) in the cells before causing myelomonocytic differentiation. MAPK activation was necessary for MJ-induced differentiation, since PD98059, an inhibitor of MAPK kinase, suppressed the differentiation induced by MJ. MJ also induced the differentiation of other human leukemia cell lines. Introduction of a double bond at the 4,5-position greatly enhanced the differentiation-inducing activity of MJ. MJ and its derivatives potently induce the differentiation of some myelomonocytic leukemia cells. One novel derivative is a particularly promising therapeutic agent for the treatment of leukemia.

Lipase-catalyzed preparation of both enantiomers of methyl jasmonate

Abstract Preparation of both enantiomeric methyl jasmonates 1 was achieved via lipase-catalyzed resolution of (±)-methyl 7-epicucurbate 3 . Lipase P (Amano) provided good selectivity both for acylation of (±)- 3 ( E =370) and hydrolysis of the corresponding acetate ( E =41). Resolution of (±)-methyl 6,7-diepicucurbate 2 gave poor results. It was found that the (6 R ,7 S )-configuration was suitable for the selective enzymatic reaction and the C-(3) stereochemistry of the substrate did not influence the enzymatic reaction.

Influenza neuraminidase operates via a nucleophilic mechanism and can be targeted by covalent inhibitors

Development of novel influenza neuraminidase inhibitors is critical for preparedness against influenza outbreaks. Knowledge of the neuraminidase enzymatic mechanism and transition-state analogue, 2-deoxy-2,3-didehydro-N-acetylneuraminic acid, contributed to the development of the first generation anti-neuraminidase drugs, zanamivir and oseltamivir. However, lack of evidence regarding influenza neuraminidase key catalytic residues has limited strategies for novel neuraminidase inhibitor design. Here, we confirm that influenza neuraminidase conserved Tyr406 is the key catalytic residue that may function as a nucleophile; thus, mechanism-based covalent inhibition of influenza neuraminidase was conceived. Crystallographic studies reveal that 2α,3ax-difluoro-N-acetylneuraminic acid forms a covalent bond with influenza neuraminidase Tyr406 and the compound was found to possess potent anti-influenza activity against both influenza A and B viruses. Our results address many unanswered questions about the influenza neuraminidase catalytic mechanism and demonstrate that covalent inhibition of influenza neuraminidase is a promising and novel strategy for the development of next-generation influenza drugs.

Echinopines A and B: sesquiterpenoids possessing an unprecedented skeleton from Echinops spinosus.

Echinopines A (1) and B (2), novel sesquiterpenoids with an unprecedented rearranged skeleton named echinopane, were isolated from the roots of Echinops spinosus. The structures were elucidated by extensive spectroscopic analysis. The relative configuration of 1 was assigned by a combination of NOESY correlations and a simulation analysis. A plausible biosynthetic pathway for echinopane was discussed.

Biodegradation of dieldrin by a soil fungus isolated from a soil with annual endosulfan applications.

An aerobic dieldrin-degrading fungus, Mucor racemosus strain DDF, was isolated from a soil to which endosulfan had been annually applied for more than 10 years until 2008. Strain DDF degraded dieldrin to 1.01 microM from 14.3 microM during a 10-day incubation at 25 degrees C. Approximately 0.15 microM (9%) of aldrin trans-diol was generated from the dieldrin degradation after a 1-day incubation. The degradation of dieldrin by strain DDF was detected over a broad range of pH and concentrations of glucose and nitrogen sources. Extracellular fluid without mycelia also degraded dieldrin. Strain DDF degraded not only dieldrin but also heptachlor, heptachlor epoxide, endosulfan, endosulfan sulfate, DDT, and DDE. Endosulfan sulfate and heptachlor were degraded by 0.64 microM (95%) and 0.75 microM (94%), respectively, whereas endosulfan and DDE were degraded by 2.42 microM (80%) and 3.29 microM (79%), respectively, and DDT and heptachlor epoxide were degraded by 6.95 microM (49.3%) and 5.36 microM (67.5%), respectively, compared with the control, which had a concentration of approximately 14 microM. These results suggest that strain DDF could be a candidate for the bioremediation of sites contaminated with various persistent organochlorine pesticides including POPs.

Synthesis and Anti-Angiogenic Activity of Cortistatin Analogs

Analogs of cortistatins, a series of anti-angiogenic compounds isolated from the Indonesian marine sponge Cortisium simplex, were synthesized from estrone by using the Suzuki-Miyaura coupling reaction as the key step. The estrone-isoquinoline hybridized compound showed selective inhibitory activity against the proliferation and VEGF-induced migration of HUVEC.