Publications by authors named "Masako Hoshino"

Hyacinthacines C and C are natural products that were isolated from Hyacinthoides non-scripta and Scilla socialis in 1999 and 2007, respectively. Despite their different H NMR and C NMR spectroscopic data, these compounds have been assigned the same structures, including absolute configurations. This work details the total synthesis of natural (+)-hyacinthacine C, whose structure is confirmed as being the C-6 epimer of that reported.

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The total synthesis of natural (+)-hyacinthacine C was achieved, which allowed correction of its initially proposed structure, as well as six additional hyacinthacine C-type compounds. These compounds were readily accessible from two epimeric anti-1,2-amino alcohols. Keeping a common A-ring configuration, chemical manipulation occurred selectively on the B-ring of the hyacinthacine C-type products through methods of syn-dihydroxylation, S2 ring-opening of a cyclic sulfate, and also employing either ( R)- or ( R, S)-α-methylallyl amine for the Petasis borono Mannich reaction.

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This study shows that the cyclization of l-DMDP thioureas to bicyclic l-DMDP isothioureas improved α-l-rhamnosidase inhibition which was further enhanced by increasing the length of the alkyl chain. The addition of a long alkyl chain, such as decyl or dodecyl, to the nitrogen led to the production of highly potent inhibitors of α-l-rhamnosidase; it also caused broad inhibition spectrum against β-glucosidase and β-galactosidase. In contrast, the corresponding N-benzyl-l-DMDP cyclic isothioureas display selective inhibition of α-l-rhamnosidase; 3',4'-dichlorobenzyl-l-DMDP cyclic isothiourea (3r) was found to display the most potent and selective inhibition of α-l-rhamnosidase, with IC value of 0.

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A 71-year-old man underwent pleural biopsy due to left pleural effusion and pleural thickening in August, 2001. An inflammatory pseudotumor (IPT) was diagnosed, and therefore systemic oral steroid therapy (prednisolone [PSL] 30 mg/day) was initiated. However, after tapering PSL to 7.

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We recently experienced one each of 2 types of recurrent respiratory papillomatosis (RRP). Case 1 (juvenile-onset type): A 30-year-old woman presenting with bloody sputum and large tumors with cavities on her chest Xray film, was referred to our hospital. She had been diagnosed with laryngeal papillomatosis when she was three years old.

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