Lawson topology of the space of formal balls and the hyperbolic topology

AbstractLet (X,d) be a metric space and BX=X×R denote the partially ordered set of (generalized) formal balls in X. We investigate the topological structures of BX, in particular the relations between the Lawson topology and the product topology. We show that the Lawson topology coincides with the product topology if (X,d) is a totally bounded metric space, and show examples of spaces for which the two topologies do not coincide in the spaces of their formal balls. Then, we introduce a hyperbolic topology, which is a topology defined on a metric space other than the metric topology. We show that the hyperbolic topology and the metric topology coincide on X if and only if the Lawson topology and the product topology coincide on BX

Synthesis of (+)-boronolide and (+)-deacetylboronolide using Pd-catalyzed carbonylation and lactonization

(+)-Boronolide and (+)-deacetylboronolide were synthesized using Pd-catalyzed CO insertion and lactonization as the key step. As to the C-13 NMR data of (+)-deacetylboronolide, the assignment at C-6 position should be revised.ArticleTETRAHEDRON LETTERS. 55(17):2822-2824 (2014)journal articl

Synthesis of both enantiomers of akolactone B and (+)-ancepsenolide

The syntheses of (+)- and (−)-akolactone B and (+)-ancepsenolide were accomplished using a Pd-catalyzed carbonylation. As to the absolute configuration of akolactone B, making a comparison of the specific rotation of both enantiomers of synthetic akolactone B and the natural compound suggests that the absolute configuration at the 4-position of akolactone B is (R).ArticleTETRAHEDRON-ASYMMETRY. 25(20-21):1367-1371 (2014)journal articl

Synthesis of legioliulin, a fluorescent isocoumarin compound, isolated from Legionella dumoffii using cyclic acylpalladation and Heck reaction

Concise synthesis of legioliulin, an isocoumarin compound isolated from Legionella dumoffii, was achieved. Isocoumarin ring of legioliulin was constructed using cyclic acylpalladation. Chain elongation was performed using Heck reaction using t-butylphosphine as a ligand. (C) 2016 Elsevier Ltd. All rights reserved.ArticleTETRAHEDRON LETTERS.57(35):3942-3944(2016)journal articl

EFFICIENT STEREOSELECTIVE SYNTHESIS OF CATECHIN TRIMER DERIVATIVE USING SILVER LEWIS ACID-MEDIATED EQUIMOLAR CONDENSATION

A stereoselective synthesis of benzylated catechin trimer under intermolecular condensasion is achieved using equimolar amount of dimeric catechin nucleophile and monomeric catechin electrophile catalyzed by AgOTf or AgBF(4). The coupled product can be transformed into procyanidin C2 by a known procedure.ArticleHETEROCYCLES. 83(4):739-742 (2011)journal articl

A CONCISE SYNTHESIS OF SOLAMIN AND CIS-SOLAMIN, MONO-THF ACETOGENINS FROM ANNONA MURICATA

A concise total synthesis of solamin (1) and cis-solamin (2) was performed using an epoxy alcohol (11) as a versatile chiral building block for synthesizing the stereoisomers of the mono-THF annonaceous acetogenins.ArticleHETEROCYCLES. 78(9):2369-2376 (2009)journal articl

Asymmetric syntheses of daedalin A and quercinol and their tyrosinase inhibitory activity

Stereoselective syntheses of daedalin A and quercinol, an enantiomer of daedalin A, is described. The tyrosinase inhibitory activities of daedalin A and quercinol were examined. The activity of quercinol was weaker than that of daedalin A at high concentration.ArticleBIOORGANIC & MEDICINAL CHEMISTRY LETTERS. 20(3):1063-1064 (2010)journal articl