Oligosaccharides play important roles in many biological events, including protein folding, cell signalling, fertilization, pathogen binding to host tissue, leukocyte trafficking and associated inflammatory response, tumour cell metastasis, and regulation of hormone and enzyme activity.[1] The development of innovative methods for selectively controlling specific functions of certain oligosaccharides has attracted much attention in the fields of chemistry, biology, and medicine. However, there have as yet been no reports of methods involving specific inhibition of function by selective degradation of a target oligosaccharide. Herein we report the target-selective degradation of an oligosaccharide induced by a light-activated small-molecule-lectin hybrid. To the best of our knowledge, this is the first successful example of targetselective degradation of an oligosaccharide by light switching under neutral conditions.With the aim of investigating a novel small molecule for degradation of oligosaccharides, we examined the anthraquinone molecule, which is found in several biologically important natural products, particularly antibiotics.[2] Certain anthraquinone derivatives have been found by Schuster and co-workers and by us to be efficient agents for DNA photocleavage. [3,4] In addition, photoinduced deterioration of cellulose by anthraquinone-related dyes has been reported, although the mechanism and the precise degradation products have not yet been elucidated.[5] On the basis of these previous findings, we expected that if an anthraquinone derivative could be made to produce a radical species by photoexcitation, [6] this species could be used for degradation not only of DNA, but also of oligosaccharide molecules.To investigate this hypothesis, we selected the anthraquinone derivative 2-hydroxymethylanthraquinone (1) owing to its solubility in aqueous media. For the oligosaccharides, we chose maltoheptaose (2), a-cyclodextrin (a-CD, 3), b-cyclodextrin (b-CD, 4), and g-cyclodextrin (g-CD, 5; Scheme 1). Although all of these oligosaccharides consist of a-d-glucose, they may be divided into two groups on the basis of their affinity for the anthraquinone derivative 1. Thus, the members of the first group, maltoheptaose and a-CD, have no specific interaction with 1, while those in the other group, b-CD and g-CD, show strong interaction with 1 owing to their ability to form an inclusion complex with 1 through hydrophobic interaction.[7] Therefore, although a simple anthraquinone derivative was used, the oligosaccharides employed clearly have different affinities for this molecule.We first examined the photoinduced oligosaccharidedegrading activity of 1 at a concentration of 300 mm against 30 mm of b-CD (10:1 1/b-CD) in 20 % acetonitrile/water solution, using a long-wavelength UV light source (365 nm, 100 W) for photoirradiation. The progress of the photodegradation reaction was monitored by HPLC. It was found that no change in the HPLC profile was obtained either by treatment of b-CD with 1 without photoirradiation or ...

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Oligosaccharides play important roles in many biological events, including protein folding, cell signalling, fertilization, pathogen binding to host tissue, leukocyte trafficking and associated inflammatory response, tumour cell metastasis, and regulation of hormone and enzyme activity.[1] The development of innovative methods for selectively controlling specific functions of certain oligosaccharides has attracted much attention in the fields of chemistry, biology, and medicine. However, there have as yet been no reports of methods involving specific inhibition of function by selective degradation of a target oligosaccharide. Herein we report the target-selective degradation of an oligosaccharide induced by a light-activated small-molecule-lectin hybrid. To the best of our knowledge, this is the first successful example of targetselective degradation of an oligosaccharide by light switching under neutral conditions.With the aim of investigating a novel small molecule for degradation of oligosaccharides, we examined the anthraquinone molecule, which is found in several biologically important natural products, particularly antibiotics.[2] Certain anthraquinone derivatives have been found by Schuster and co-workers and by us to be efficient agents for DNA photocleavage. [3,4] In addition, photoinduced deterioration of cellulose by anthraquinone-related dyes has been reported, although the mechanism and the precise degradation products have not yet been elucidated.[5] On the basis of these previous findings, we expected that if an anthraquinone derivative could be made to produce a radical species by photoexcitation, [6] this species could be used for degradation not only of DNA, but also of oligosaccharide molecules.To investigate this hypothesis, we selected the anthraquinone derivative 2-hydroxymethylanthraquinone (1) owing to its solubility in aqueous media. For the oligosaccharides, we chose maltoheptaose (2), a-cyclodextrin (a-CD, 3), b-cyclodextrin (b-CD, 4), and g-cyclodextrin (g-CD, 5; Scheme 1). Although all of these oligosaccharides consist of a-d-glucose, they may be divided into two groups on the basis of their affinity for the anthraquinone derivative 1. Thus, the members of the first group, maltoheptaose and a-CD, have no specific interaction with 1, while those in the other group, b-CD and g-CD, show strong interaction with 1 owing to their ability to form an inclusion complex with 1 through hydrophobic interaction.[7] Therefore, although a simple anthraquinone derivative was used, the oligosaccharides employed clearly have different affinities for this molecule.We first examined the photoinduced oligosaccharidedegrading activity of 1 at a concentration of 300 mm against 30 mm of b-CD (10:1 1/b-CD) in 20 % acetonitrile/water solution, using a long-wavelength UV light source (365 nm, 100 W) for photoirradiation. The progress of the photodegradation reaction was monitored by HPLC. It was found that no change in the HPLC profile was obtained either by treatment of b-CD with 1 without photoirradiation or ...

Anthraquinone Derivatives as a New Family of Protein Photocleavers. -The ability of the novel compounds (I) and (II) to act as protein photocleavers is assessed and the results are discussed. -(SUZUKI, A.; HASEGAWA, M.; ISHII, M.; MATSUMURA, S.; TOSHIMA*, K.; Bioorg. Med. Chem. Lett. 15 (2005) 20, 4624-4627; Dep. Appl. Chem., Fac. Sci. Technol., Keio Univ., Kohoku, Yokohama 223, Japan; Eng.) -K. Schneider 02-196