• Bulletin of the Korean Chemical Society
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• v.32 no.1
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• pp.153-156
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• 2011

A concise synthesis of (${\pm}$)-rhinacanthin A is achieved in two steps by epoxidation of dehydro-$\alpha$-lapachone, followed by chemo- and regioselective reduction. Dehydro-$\alpha$-lapachone was also synthesized in two steps starting from 4-methoxy-1-naphthol by ethylenediamine diaetate (EDDA)-catalyzed benzopyran formation and a CAN-mediated oxidation reaction. $\beta$-Lapachone was synthesized in three steps from 4-methoxy-1-naphthol by benzopyran formation, catalytic hydrogenation, and Jones oxidation. As additional reactions, synthesis of pyranonaphthoquinone derivatives with the pyranokunthone B skeleton has been achieved in a single step from readily available 2-hydroxy-6-methoxy-1,4-naphthoquinone and 2-hydroxy-7-methoxy-1,4-naphthoquinone.

• Bulletin of the Korean Chemical Society
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• v.33 no.6
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• pp.2087-2090
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• 2012

• Bulletin of the Korean Chemical Society
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• v.13 no.4
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• pp.351-352
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• 1992

• Bulletin of the Korean Chemical Society
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• v.32 no.spc8
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• pp.2921-2927
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• 2011

This paper describes efficient synthetic approaches for isolating biologically interesting natural pyranochalcones and their unnatural derivatives from Mallotus Philippensis. The key strategies involve ethylenediamine diacetate-catalyzed benzopyran formation reactions and base-catalyzed aldol reactions.

• Bulletin of the Korean Chemical Society
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• v.35 no.8
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• pp.2385-2390
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• 2014

Novel 2,6-difuctionalized 2H-benzopyrans were synthesized and evaluated for a sphingosylphosphorylcholine(SPC) inhibitor. The synthetic 2H-benzopyrans 1c and 3a showed high potency in SPC-induced cell proliferation assay ($IC_{50}$ < 20 nM). Neither hERG $K^+$ channel binding (> $10{\mu}M$) nor CYP inhibitions (> $10{\mu}M$) were observed. Also, the simple structure-activity relationship (SAR) results were obtained from analysis of 2H-benzopyran derivatives 1-3 and the anti-SPC effect of 2H-benzopyran 1c was confirmed by a HUVEC tube formation assay.

• Journal of Evidence-Based Herbal Medicine
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• v.3 no.1
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• pp.35-41
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• 2010

From the roots of Angelica dahurica Bentham et Hooker (Umbelliferae), three known coumarin derivatives have been isolated and identified as 8-(2-hydroxy-3-methoxy-3-methylbutyloxy) psoralen, 5,8-di(2,3-dihydroxy-3-methylbutyloxy) psoralen, 9-[3-($\beta$-D-glucopyranosyloxy)-2-hydroxy-3-methylbutoxy]-7H-furo[3,2-g][1]benzopyran-7-one. This is the first report of the occurrence of these compounds in this plant. These three compounds were tested for activity in septic shock model. Among these compounds, 2 showed relatively strong preventive activity against septic shock.

• Biomolecules & Therapeutics
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• v.14 no.2
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• pp.102-105
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• 2006

We examined the effects of psoralen derivatives on a rapidly activating delayed rectifier $K^+$ channel (hKv1.5) cloned from human heart and stably expressed in $Ltk^-$ cells. Using the whole cell configuration of the patch-clamp technique, we found that the five psoralen derivatives inhibited hKv1.5 current. Especially, 4-(2-Propenyloxy)-7H-furo[3,2-g][1]benzopyran-7-one (compound 5) was more potent than the inhibition of the hKv1.5 current of psoralen. The compound 5 inhibited the hKv1.5 current in a concentration-, time-, and voltage-dependent manner. These results suggest that the compound 5 is an excellent candidate as an antiarrhythmic drug for atrial fibrillation.

• Journal of the Korean Chemical Society
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• v.55 no.2
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• pp.218-229
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• 2011

We have involved the imine compound 1 in condensations with various nitrogenous reagents including hydrazine hydrate to construct differently substituted pyrimidines. One of the pyrimidines so obtained was further subjected to interactions with different reagents such as propionic acid, formic acid, ethyl chloroformate, acdetic anhydride, carbon disulphide, cyanogene bromide, triflauroacetic acid and ethyl chloroacetate which resulted in the formation of annulated heterocyclic systems as pairs of isomers in most cases as a result of Dimroth-type rearrangement.