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1.
A simple, novel, and an efficient synthesis of α-hydroxy phosphonates (3a–d) and phosphinates (5a–f) has been accomplished from febuxostat aldehyde (1) with various dialkylphosphites (2) and dialkylphosphinates (4) in the presence of 1, 4-dimethylpiperazine as a strong base with good to excellent yields (78%–95%) is reported. The structures of the title compounds were established by elemental analysis and spectral data (IR, 1H, 13C and 31P NMR, and LC-MS). All the title compounds (3a–d) and (5a–f) were tested for their antimicrobial and antioxidant activities. Bioassay results reveal that a few of the title compounds exhibited promising antimicrobial and antioxidant activities. 相似文献
2.
Kanhokthron Boonkitpattarakul Darunee Soorukram Patoomratana Tuchinda Vichai Reutrakul Manat Pohmakotr 《Journal of fluorine chemistry》2011,132(11):987-990
The synthetic utility of α,α-difluoro-α-phenylsulfanyl-α-trimethylsilylmethane (PhSCF2SiMe3; 1) as a difluoromethyl building block providing a general strategy to α,α-difluoromethyl aryl ketones was demonstrated. Oxidation, by using m-chloroperoxybenzoic acid, of the readily available 1-aryl-2,2-difluoro-2-phenylsulfanyl-1-trimethylsiloxyethanes obtained from fluoride-catalyzed nucleophilic addition of PhSCF2SiMe3 with aromatic aldehydes followed by flash vacuum pyrolytic elimination provided α,α-difluoromethyl aryl ketones in moderate overall yields. 相似文献
3.
Toru Minami Ryoji Kouno Tatsuo Okauchi Mitsuharu Nakamura Junji Ichikawa 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):689-692
The α-phosphonovinyl anions, generated in situ from treatment of β-hetero-substituted vinyl-phosphonates 1a-c with LDA (or LTMP), were trapped with various electrophiles such as chlorotriorganosilanes, chlorotrimethylgermane, chlorotriorganotins, dimethyl disulfide, and halogen to afford the corresponding β-hetero-substituted α-functionalized vinylphosphonates 2–14 in good to excellent yields. The Friedel-Crafts reaction of α-(silyl) or α-(germyl)phosphonoketene dithioacetals 2, 9 or 4 with acid chlorides gave α-acylated phosphonoketene dithioacetals 15–19 in 53–91 % yields. The palladium-catalyzed cross-coupling reaction of β-ethoxy-α-(tributylstannyl)vinylphosphonate 13 with a variety of organic halides (R = acyl, allyl, aryl etc.) provided β-ethoxy-α-substituted vinylphosphonates 20–25 in good to moderate yields. The palladium-mediated cross-coupling reaction of α-(iodo)-vinyl-phosphonates 7, 14 with terminal acetylenes afforded α-alkynylated vinylphosphonates 26–29 in 69–83 % yields. 相似文献
4.
《合成通讯》2013,43(11):1709-1713
ABSTRACT The abstraction of the acid hydrogen of O-tosylhydroximates 1 by sodium ethylate, then nucleophilic attack of the excess of sodium ethylate at the more hindred carbond atom of azirine 2 and aziridine 3 intermediates to give the α-aminoorthoesters (35–45% yields). The α-aminoorthoester 4a is transformed into α-iminoorthoesters 5a (63% yield) and α-amidoorthoester 6a (65% yield). 相似文献
5.
Abstract Total synthesis of two arabidopyrones, iso-arabidopyl alcohol (1) and iso-arabidopic acid (2) isolated from Arabidopsis thaliana was achieved for the first time using Claisen condensation and Wittig reaction as the key steps. In addition, arabidopic acid (4) was synthesized from the methyl ester of arabidopyl alcohol (3). Thus, chemical synthesis of the unique natural α-pyrones 1–4 was accomplished with a short synthetic route by a systematic approach from readily available substances. 相似文献
6.
Quan-Wen Liu Cai-Hua Chen Xiao-Feng Wang Kun Jiang Shi-Jin Qu Yi-Ru Dai 《Natural product research》2019,33(1):41-46
Six triterpenoids (1–6), four megastigmanes (7–10) and five hydroxycinnamic acid derivatives (11–15) were isolated from the aerial part of Anisomeles indica (Lamiaceae). Of these components, compound 1 was identified to be a new triterpenoid with the structure of 2α,3α,19α-trihydroxyurs-12,20(30)-dien-28-oic acid based on extensive analysis of MS, 1D and 2D NMR spectroscopic data, while compounds 2–13 were obtained for the first time from Anisomeles species. 相似文献
7.
M. Anil Kumar Kap Duk Lee 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):899-905
Abstract A simple and efficient method has been developed for the one-pot synthesis of α-aminophosphonates using polyethylene glycol (PEG) as a green reaction media. 相似文献
8.
Ian W. J. Still Wang Daoquan 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):83-89
Abstract The reactions of a series of O-silylated α-ketols with trimethylsilyl cyanide have been investigated. Formation of the expected 0-trimethylsilyl cyanohydrins as major products has been shown to be accompanied by the hitherto unsuspected formation of a disiloxane by a proposed intramolecular SN2 displacement mechanism. The latter reaction is, surprisingly, independent of the substitution pattern in the silylated ketol. Formation of the side-product, however, increases in all cases with increasing dilution. The α,β-epoxynitrile 9, a second side-product expected, along with the observed disiloxane, by our proposed mechanism was synthesized by an unambiguous route. A control experiment showed the epoxynitrile to be completely destroyed under the usual conditions of reaction with trimethylsilyl cyanide. 13C NMR data have been obtained for most of the compounds in this study. 相似文献
9.
Sui Xianjin Shi Sha Muge Qi Zhengxi Zhang Yuyao Yang Haibo Wu 《Natural product research》2018,32(13):1518-1524
A new germacrenolide (1) and fourteen known terpenoids (2–15) were isolated from the barks of Magnolia maudiae (Dunn) Figlar (Magnoliaceae). The structure of (7αH,11βH)-2α,8α-dihydroxy-4α,5β-epoxy-germacr-1(10)-en-6α,12-olide (1) was elucidated by physical and spectroscopic data analysis, including 1D, 2D NMR and HR-ESI-MS. Lyratol F (9) was isolated from Magnolia for the first time. The structures of known compounds were established by comparing their spectroscopic data with those in literatures. 相似文献
10.
The First Mitsunobu Protocol for Efficient Synthesis of α-Acyloxyphosphonates Using 4,4′-Azopyridine
Nasser Iranpoor Habib Firouzabadi Dariush Khalili 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2166-2171
Abstract This is the first report on applying the Mitsunobu protocol for the synthesis of various α-acyloxyphosphonates using 4,4′-azopyridine and PPh3 with diverse aromatic and aliphatic carboxylic acids. Under these conditions, diethyl azodicarboxylate (DEAD) as the traditional reagent for Mitsunobu reaction is not efficient. The insoluble pyridine hydrazine byproduct can be simply isolated and recycled to its azopyridine by an oxidation reaction and reused again. [Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental resource: Characterization data of compounds 3a–3z2 and NMR spectra.] GRAPHICAL ABSTRACT 相似文献
11.
Nantiya Joycharat Papawarin Issarachote Chonlatid Sontimuang Supayang Piyawan Voravuthikunchai 《Natural product research》2018,32(11):1291-1294
Albizia myriophylla Benth. is a medicinal herb which is used as a traditional remedy for various ailments including diabetes in Thailand. In our continued investigation of the biological activity of A. myriophylla, the ethanol extract, fractions and the isolated compounds from the wood of this plant were evaluated for in vitro α-glucosidase inhibition using spectrophotometric method. The plant ethanol extract and its different fractions possessed α-glucosidase inhibitory activity in a concentration-dependent manner. Dichloromethane fraction of the wood ethanol extract exhibited the highest percent inhibition against α-glucosidase (69.30%) among all fractions. Subsequent α-glucosidase inhibition assay proved that indenoic acid (1), 8-methoxy-7, 3′,4′-trihydroxyflavone (2) and 3,4,7,3′-tetrahydroxyflavan (3) were partially rational for antidiabetic effect of this plant species. Among these compounds, 3 (IC50 98.59 μg/mL) exhibited potent inhibition of α-glucosidase, compared with a positive control acarbose (IC50 125 μg/mL). The inhibitory effect towards α-glucosidase of compounds 1–3 was reported herein for the first time. 相似文献
12.
Dinh Tri Mai Tien Dung Le Tan Phat Nguyen Nhat Minh Phan Huu An Nguyen Thi Thanh Phuc Nguyen 《Natural product research》2015,29(15):1437-1441
From the fruit of Pandanus tectorius Parkinson ex Du Roi, one new (1) and six known aldehyde compounds (2–7) were isolated by various chromatography methods. Based on their spectroscopic data, these compounds were identified as (Z)-4-hydroxy-3-(4-hydroxy-3-methylbut-2-en-1-yl) benzaldehyde (1), p-hydroxybenzaldehyde (2), syringaldehyde (3), (E)-ferulaldehyde (4), (E)-sinapinaldehyde (5), vanillin (6) and 5-hydroxymethylfurfual (7). The α-glucosidase inhibitory activity of all compounds was measured. The isolated compounds (1–6) showed better α-glucosidase inhibitory activity (IC50 values ranging from 36.5 to 192.4 μM) than the standard drug acarbose (IC50 = 214.5 μM). 相似文献
13.
14.
William T. Murray Anne Pautard-cooper Nita A. Eskew Slayton A. Evans Jr 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):101-104
Abstract The kinetics of Lewis acid-mediated decomposition and definitions of the synthetic applicability of 1,3,2λ5-dioxaphospholanes for (i) the syntheses of highly-hindered epoxides, and (ii) the stereospecific functionalizations of stereocenters in 1,2-diol arrays are described. 相似文献
15.
Tan Phat Nguyen Tien Dung Le Phan Nhat Minh Bui Trong Dat Nguyen Kim Tuyen Pham Thi My Lien Do 《Natural product research》2016,30(21):2389-2395
From the fruit of Pandanus tectorius Parkinson ex Du Roi, one new dihydrofurocoumarin, named pandanusin A (1) and 15 known compounds, including one furanocoumarin (2), two coumarins (3, 4), four lignans (5–8), one neolignan (9), two flavonoids (10, 11), three phenolics (12–14), one monoglyceride (15) and one monosaccharide (16) were isolated by various chromatography methods. Among them, compounds (3–5) were obtained from the Pandanus genus for the first time and compounds (9–14, 16) were reported from this species for the first time. Their structures were elucidated by HR–ESI–MS, NMR 1D and 2D experiments and comparison with previous reported data. The α-glucosidase inhibitory activity of all compounds was measured. The isolated compounds (1–12, 14) showed better α-glucosidase inhibitory activity (IC50 = 42.2, 36.5, 84.7, 73.2, 40.8, 26.7, 76.5, 33.8, 68.1, 14.4, 22.1, 81.5, 43.8 μM, respectively) than the standard drug acarbose (IC50 = 214.5 μM). 相似文献
16.
Mariana G. Vallejo Marcos E. Corzo María Gabriela Ortega 《Natural product research》2020,34(9):1270-1275
Abstract12α-hydroxy-N-demethyl-sauroxine (1), another new Lycopodium alkaloid from the Lycodane group, was isolated from Phlegmariurus saururus (Lam.) B. Øllg. (Lycopodiaceae). Elucidation of the chemical structure and relative stereochemistry were stated by spectroscopic data and chemical correlation. In addition, the inhibitory activity on acetylcholinesterase for 1 was determined as well as for N-methyllycodine (2), a derivative with the same nucleus, previously identified in P. saururus (IC50 = 33.8?±?0.8?μM and 547.5?±?0.5?μM, respectively) and N-demethylsauroxine (3) whose inhibition in the actual conditions was better than the previously informed. 相似文献
17.
AbstractA simple, mild, straightforward, efficient and eco-friendly protocol has been developed for the synthesis of a series of α-aminonitriles via the one-pot three-component Strecker reactions between various aldehydes, amines and trimethylsilyl cyanide using a catalytic amount of mandelic acid as a naturally occurring, low-cost, efficient organo-catalyst under solvent-free conditions at room temperature. Under the same optimized conditions synthesis of α-aminophosphonates were also achieved via the one-pot three-component Kabachnik-Fields reactions of aldehydes, amines and triethyl phosphate. 相似文献
18.
AbstractGermicidin N (3-ethyl-4-hydroxy-6-[(1S, 2?R)?2-hydroxy-1-methylpropyl]-2H-pyran-2-one, 1), a new α-pyrone from the extracts of a Streptomyces sp. derived from marine algae, has been synthesized for the first time as four possible diastereomers from chiral β-hydroxyester ((S)?6 and (R)?9) through the stereoselective alkylation, Claisen condensation followed by cyclization in a straightforward manner. 相似文献
19.
Xuedan Huang Mingzhu Xu Tatsuya Shirahata Wei Li Kazuo Koike Akiko Kojima-Yuasa 《Natural product research》2018,32(12):1459-1462
There is no drug administration-approved therapy for non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH). In this study, eight compounds, gallic acid (1), methyl gallate (2), corilagin (3), 3,4,8,9,10-pentahydroxydibenzo[b,d]pyran-6-one (4), repandinin B (5), (Z)-3-hexenyl-β-D-glucopyranoside (6), (+)-lyoniresinol-3α-O-α-L-rhamnopyranoside (7) and mallophenol A (8) were isolated from the active fractions of Mallotus furetianus. Three compounds, (6, 7 and 8) revealed potent anti-steatosis activity in the oleic acid (OA)-induced steatosis cell model, with the minimum effective concentration of 0.05 (6), 0.0005 (7) and 0.0005 (8) μg/mL, which were much lower than the control compound, fibrate (72.4 μg/mL). 相似文献
20.
Zhi-Hua Yu De-Qing Shi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):1746-1752
A series of novel α-amino phosphonate derivatives containing the thiazole and pyrazole moieties 3 were synthesized by the Mannich-type reaction of substituted pyrazole-aldehyde 1, 2-amino-5-ethoxycarbonyl-4-methyl-thiazole 2, and dialkyl phosphites or triphenyl phosphite in the presence of a Lewis acid such as magnesium perchlorate as the catalyst under solvent-free conditions. Their structures were clearly confirmed by spectroscopy data (IR, 1H NMR, 31P NMR, MS) and elemental analysis. The results of a preliminary bioassay (in vitro) indicated that some of the title compounds 3 possessed moderate herbicidal activities against dicotyledonous plants (Brassica campestris L) or monocotyledonous plants (Echinochloa crus-galli) at the concerntration of 100 mg/L. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. 相似文献