Showing papers by "Patoomratana Tuchinda published in 2012"
TL;DR: Prenylated caged xanthones, both naturally occurring and synthetic analogues, have been identified as promising bioactive compounds, especially for anticancer agents.
Abstract: Context: Prenylated caged xanthones are “privileged structure” characterized by the presence of the unusual 4-oxo-tricyclo[4.3.1.03,7]dec-8-en-2-one scaffold. The natural sources of these compounds confines mainly in the Garcinia genus in the family of Guttiferae. Gambogic acid is the most abundant substance and most of the studies have been done on this compound, particularly as a new potential antitumor agent. The history, sources, structural diversity, and biological activities of these compounds are covered.Objective: This review is written with the intention to provide additional aspects from what have been published of prenylated caged xanthones, including history, sources, structural diversity, and biological activities.Methods: This review has been compiled using information from a number of reliable references mainly from major databases including SciFinder, ScienceDirect, and PubMed.Results: More than 120 prenylated caged xanthones have been found in the plant genera Garcinia, Cratoxylum, and Da...
71 citations
TL;DR: Pre-treatment of rat primary cortical cell cultures with 25-250μM NTF significantly attenuated 10μM Aβ(1-42)-induced neuronal death in a dose-dependent manner and suggest that the protective effect of NTF against Aβ
35 citations
TL;DR: Fluoride-catalyzed stereoselective nucleophilic addition of PhSCF(2)SiMe(3) (1) to α-carboethoxycycloalkanones afforded the corresponding gem-difluoromethylenated bicyclic compounds, which underwent ring-expansion followed by the Baeyer-Villiger-type oxidation of the resulting macrocyclic ketone intermediates.
33 citations
TL;DR: The fluoride-catalyzed nucleophilic addition of PhSCF(2)SiMe(3) (1) to chiral imides was achieved in satisfactory yields to provide mixtures of syn- and anti-isomers 6-9 with moderate to good diastereoselectivities.
Abstract: An asymmetric synthesis of gem-difluoromethylenated dihydroxypyrrolizidines and indolizidines is described. The fluoride-catalyzed nucleophilic addition of PhSCF2SiMe3 (1) to chiral imides was achieved in satisfactory yields to provide mixtures of syn- and anti-isomers 6–9 with moderate to good diastereoselectivities. Reductive cleavage of the phenylsulfanyl group followed by intramolecular radical cyclization of the syn-isomers 6–9 occurred under refluxing conditions to afford the corresponding gem-difluoromethylenated 1-azabicyclic compounds 10–13 in moderate yields as a separable mixture of cis- and trans-isomers. The cis-isomers of compounds 10 and 12 and trans-13 were readily transformed to gem-difluoromethylenated dihydroxypyrrolizidines 20 and 27 and indolizidine 28, respectively, by reductive cleavage of the hydroxyl group and organometallic addition followed by hydrogenolysis.
26 citations
TL;DR: In this article, the effects of chitosan/sodium dodecyl sulfate (CS/SDS)-stabilized emulsions of oil extract from Zingiber cassumunar Roxb. or plai oil were prepared in a one-step emulsification process.
25 citations
TL;DR: The enantioselective synthesis of a pyranonaphthoquinone from a Thai endemic plant, Ventilago harmandiana, has been achieved as mentioned in this paper.
Abstract: The enantioselective synthesis of a naturally occurring pyranonaphthoquinone iso- lated from a Thai endemic plant, Ventilago harmandiana, has been achieved. L-Rhamnose and gallic acid were used as the starting materials. A new C-1-glycosidation of L-rhamnal with trimethyl aluminum in the presence of a catalytic amount of ytterbium(III) triflate was developed. A new reagent, PhSCF 2 H/SnCl 4 , for the formylation of partially deactivated and hindered aromatic compounds has been introduced. Phenylthiophthalide was used efficiently as a cycloannulating agent in the Hauser cycloannulation reaction, employing slightly excess lithium t-butoxide as a base with a catalytic amount of lithium chloride. The synthetic route developed is applicable for the synthesis of other analogues with substituents at the aromatic and pyran rings.
21 citations
TL;DR: Four new flavones were found to inhibit DNA topoisomerase IIα activity, which may be responsible for the observed cytotoxic activity in Gardenia carinata cell lines.
17 citations
TL;DR: In this article, the authors investigated the anticancer potential of cleistanthoside A tetraacetate (CAT), a derivative of CSA from Phyllanthus taxodiifolius Beille on human lung cancer cells.
11 citations
TL;DR: A general strategy for the preparation of gem-difluoromethylenated cyclopentanols has been demonstrated in this paper, which involves sequential fluoride-catalyzed nucleophilic addition of α,α-Difluoro-α-phenylsulfanyl, α-trimethylsilylmethane (PhSCF 2 SiMe 3 ; 1 ) to homoallyl ketones followed by intramolecular radical cyclization.
11 citations
TL;DR: Bioassay-guided fractionation and purification of the aerial parts of Piper sub Multinerve led to the isolation of a new conjugated amide-dimer, submultinamide A, along with 11 known compounds, which showed significant activities in the anti-syncytium assay and the HIV-1 reverse transcriptase assay.
9 citations
TL;DR: In this paper, the diastereoselective reaction of the vicinal dianion, generated from di-()-menthyl succinate, with electrophiles, i.e., symmetrical ketones, aldehydes, and benzyl bromide, was examined.
Abstract: The diastereoselective reaction of the vicinal dianion, generated from di-()-menthyl succinate, with electrophiles, i.e. symmetrical ketones, aldehydes, and benzyl bromide was examined. The reactions with ketones and benzyl bromide gave products in good yields, however, with poor diastereoselectivities. The reaction with aldehydes in the presence of ZnCl2 preferably gave the anti-aldol adducts, which subsequently led to cis-paraconic esters again with moderate diastereoselectivity.
TL;DR: In this paper, a combination of Bu3P/phenol in THF was found being optimum conditions giving the corresponding MBH adducts with high diastereoisomeric ratios.
Abstract: The MoritaBaylisHillman (MBH) reactions of (4S,5R,7R,8R)- and (4R,5R,7R,8R)-4-hydroxy-7,8-dimethoxy-7,8-dimethyl-6,9-dioxaspiro[4.5]dec-2-en-1-ones (2 and 3, resp.) with aldehydes using various catalysts were studied. A combination of Bu3P/phenol in THF was found being optimum conditions giving the corresponding MBH adducts with high diastereoisomeric ratios. After separation, each stereomerically pure isomer of the MBH adducts was subjected to hydrolysis employing 1% aq. CF3COOH (TFA) in a water bath of an ultrasonic cleaner to afford the corresponding polyhydroxylated cyclopentenones in good yields.
TL;DR: Cleistanthoside A tetraacetate isolated from P. taxodiifolius Beille at the given doses did not show mutagenic and genotoxic activities both in vitro and in vivo studies.
Abstract: Cleistanthoside A tetraacetate isolated from Phyllanthus taxodiifolius Beille is claimed to inhibit cancer cell growth, but their toxicity is not reported. Mutagenic and genotoxic effects of cleistanthoside A tetraacetate were investigated in this study. The bacterial reverse mutation (Ames) test using a pre-incubation method was performed in order to determine the mutagenic toxicity of cleistanthoside A tetraacetate at doses ranging from 1, 25, 50 and 100 μg/ plate. In vitro and bone marrow micronuclei were used to determine genotoxicity. Cleistanthoside A tetraacetate at the given doses did not show mutagenic toxicity against the tests of bacterial strains of TA98 and TA100 in conditions with and without S9. There was no significance of in vitro and bone marrow micronucleated polychromatic erythrocyte at the given doses of isolate compared to the control. Cleistanthoside A tetraacetate isolated from P. taxodiifolius Beille at the given doses did not show mutagenic and genotoxic activities both in vitro and in vivo studies.
Key words: Toxicity, cleistanthoside A tetraacetate, Ames test, micronucleus.
TL;DR: The pathway to gem-difluoro cyclopentanols (IV) and (V) involves sequential fluoride-catalyzed addition of difluor(phenylsulfanyl)trimethylsilylmethane (II) to homoallylic ketones (I) and subsequent intramolecular radical cyclization.
Abstract: The pathway to gem-difluoro cyclopentanols (IV) and (V) involves sequential fluoride-catalyzed addition of difluoro(phenylsulfanyl)trimethylsilylmethane (II) to homoallylic ketones (I) and subsequent intramolecular radical cyclization.
01 Jan 2012
TL;DR: MUC-30 is a promising potent anti-proliferative agent for MCF-7 cells by inducing apoptosis and is important for further development of this compound as a new therapeutic agent for cancer treatment.
Abstract: Introduction. Currently, a number of semi-synthetic of natural plant compounds have been developed to improve its effectiveness for treatment of cancers. In the present study, we investigated the anti-proliferative activity and apoptosis induction of MUC-30 in human breast cancer cells (MCF-7). MUC-30, a semi- synthetic analog of lignan, isolated from Phyllanthus taxodiifolius Beille (Krai Hang Nak). Methods. MCF-7 cells were treated with various concentrations of MUC-30 (0.01-10 µM) for 24-72 h and cell viability was evaluated by MTT assay. The anti-proliferative effect of the compound to MCF-7 cells via apoptosis pathway was determined by using DAPI assay, flow cytometry analysis, and the protein expression of PARP-1. Results. MUC-30 potently inhibited the proliferation of MCF-7 cells in a concentration- and time-related manners. Its IC50 (concentration that inhibits 50% of cell growth) was approximately 0.23 ± 0.07 µM at 72 h. The compound induced morphological changes of nucleus, caused an accumulation of apoptotic cell in subG0 phase, and induced the expression of cleaved PARP-1. Conclusion. MUC-30 is a promising potent anti-proliferative agent for MCF-7 cells by inducing apoptosis. The result of this study is important for further development of this compound as a new therapeutic agent for cancer treatment. J Physiol Biomed Sci. 2012; 25(1): 19-22
TL;DR: Fluoride-catalyzed stereoselective nucleophilic addition of silane (II) to cyclic ketones gives cis-isomers (IV) as the major products as mentioned in this paper.
Abstract: Fluoride-catalyzed stereoselective nucleophilic addition of silane (II) to cyclic ketones gives cis-isomers (IV) as the major products.
TL;DR: In this article, a compound (I) can be used as a building block for the synthesis of α,α-difluoromethyl aryl ketones.
Abstract: Compound (I) can be used as building block for the synthesis of α,α-difluoromethyl aryl ketones.
TL;DR: The enantioselective synthesis of a pyranonaphthoquinone from a Thai endemic plant, Ventilago harmandiana, has been achieved.
Abstract: The enantioselective synthesis of a naturally occurring pyranonaphthoquinone iso- lated from a Thai endemic plant, Ventilago harmandiana, has been achieved. L-Rhamnose and gallic acid were used as the starting materials. A new C-1-glycosidation of L-rhamnal with trimethyl aluminum in the presence of a catalytic amount of ytterbium(III) triflate was developed. A new reagent, PhSCF 2 H/SnCl 4 , for the formylation of partially deactivated and hindered aromatic compounds has been introduced. Phenylthiophthalide was used efficiently as a cycloannulating agent in the Hauser cycloannulation reaction, employing slightly excess lithium t-butoxide as a base with a catalytic amount of lithium chloride. The synthetic route developed is applicable for the synthesis of other analogues with substituents at the aromatic and pyran rings.