- Inhibition of catechol-O-methyltransferase (COMT) by some plant-derived alkaloids and phenolics
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In this study, as an alternative to the medicines, natural compounds extracted from plant species (Peganum harmala, Cistus parviflorus and Vitex agnus-cactus) were investigated in order to inhibit the catechol-O-metyhltranferase (COMT) activity. In fluoro
- Yalcin, Dilek,Bayraktar, Oguz
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Read Online
- OBTUSININ - A NEW COUMARIN FROM Haplophyllum obtusifolium
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The epigeal part of Haplophyllum obtusifolium collected in Ustyurt has yielded β-sitosterol, isofraxetin, and a new coumarin - obtusinin - with the composition C15H18O6, mp 135-137 deg C (methanol), D20 +140.9 deg (c 0.44; chloroform).The structure of obtusinin has been established on the basis of the results of a study of UV, IR, PMR, and mass spectra and also of some chemical transformations (hydrolysis, acetylation).
- Matkarimov, A. D.,Batirov, E. Kh.,Malikov, V. M.,Seitmuratov, E.
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Read Online
- A COUMARIN GLUCOSIDE FROM XEROMPHIS OBOVATA
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From root bark of Xeromphis obovata three coumarins have been isolated: scopoletin, its 7-β-D-glucopyranoside (scopolin) and the new β-D-apiosyl-(1" -> 6)-β-D-glucopyranoside of scopoletin, named xeroboside.Also two iridoids, deacetylasperulosidic acid methyl ester and gardenoside, have been isolated and identified as the corresponding acetyl derivetives. Key Word Index-Xeromphis obovata; Rubiaceae; coumarins; iridoids; xeroboside.
- Sibanda, S.,Ndengu, B.,Multari, G.,Pompi, V.,Galeffi, C.
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- Glycosides of Atractylodes ovata.
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A new coumarin glycoside and a new glycoside of an acetylene derivative were isolated from the water-soluble portion of the methanolic extract of Atractylodes ovata rhizome together with eight known compounds. Their structures were characterized as scopoletin beta-D-xylopyranosyl-(1-->6)-beta-D-glucopyranoside and (2E)-2-decene-4,6-diyne-1,8-diol 8-O-beta-D-apiofuranosyl-(1-->6)-beta-D-glucopyranoside, respectively, based on chemical and spectroscopic investigations. A comparison of the polar constituents among Atractylodes japonica, Atractylodes lancea, and A. ovata is led to the conclusion that A. ovata is distinguishable from A. lancea and A. japonica, as also shown by phylogenetic analysis.
- Kitajima, Junichi,Kamoshita, Akane,Ishikawa, Toru,Takano, Akihito,Fukuda, Tatsuo,Isoda, Susumu,Ida, Yoshiteru
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Read Online
- Synthesis and structure-activity relationship of coumarins as potent Mcl-1 inhibitors for cancer treatment
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Myeloid cell leukemia-1 (Mcl-1) is a validated and attractive target for cancer therapy. Over-expression of Mcl-1 in many cancers allows cancer cells to evade apoptosis and contributes to their resistance to current chemotherapeutics. In this study, more than thirty coumarin derivatives with different substituents were designed and synthesized, and their Mcl-1 inhibitory activities evaluated using a fluorescence polarization-based binding assay. The results showed that the catechol group was a key constituent for Mcl-1 inhibitory activity of the coumarins, and methylation of the catechol group led to decreased inhibitory activity. The introduction of a hydrophobic electron-withdrawing group at the C-4 position of 6,7-dihydroxycoumarin, enhanced Mcl-1 inhibitory capacity, and a hydrophilic group in this position was unbeneficial to the inhibitory potency. In addition, the introduction of a nitrogen-containing group to the C-5 or C-8 position, which allowed an intramolecular hydrogen bond, was also unfavorable for Mcl-1 inhibition. Among all coumarins tested, 4-trifluoromethyl-6,7-dihydroxycoumarin (Cpd 4) displayed the most potent inhibitory activity towards Mcl-1 (Ki = 0.21 ± 0.02 μM, IC50 = 1.21 ± 0.56 μM, respectively), for which the beneficial effect on taxol resistance was also validated in A549 cells. A strong interaction between Cpd 4 and Mcl-1 in docking simulations further supported the observed potent Mcl-1 inhibition ability of Cpd 4. 3D-QSAR analysis of all tested coumarin derivatives further provides new insights into the relationships linking the inhibitory effects on Mcl-1 and the steric-electrostatic properties of coumarins. These findings could be of great value for medicinal chemists for the design and development of more potent Mcl-1 inhibitors for biomedical applications.
- Xia, Yang-Liu,Wang, Jing-Jing,Li, Shi-Yang,Liu, Yong,Gonzalez, Frank J.,Wang, Ping,Ge, Guang-Bo
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- Scopoletin benzene sulfonyl furazan oxynitride derivatives as well as preparation method and application thereof
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The invention belongs to the field of biological medicines, and discloses scopoletin benzene sulfonyl furazan oxynitride derivatives as shown in a formula I, wherein R is selected from H, acetamido and amino, X is selected from -(CH2)n-, and n is an integer of 2-6. Compared with scopoletin, the derivatives have a stronger proliferation inhibition effect on MDA-MB-231, MCF-7, HepG2 and A549 cell strains, the proliferation inhibition effect on tumor cells is remarkably superior to that of scopoletin, and the derivatives are expected to become a new anti-tumor drug. The invention also discloses an application of the derivatives in the preparation of antitumor drugs.
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Paragraph 0039; 0048-0052
(2020/06/20)
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- Novel NO-releasing scopoletin derivatives induce cell death via mitochondrial apoptosis pathway and cell cycle arrest
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A series of phenylsulfonyfuroxan-based NO-releasing scopoletin derivatives were designed and synthesized in the study. All target compounds showed significantly improved antiproliferative activity against four cancer cell lines (MDA-MB-231, MCF-7, HepG2 and A459) and lower cytotoxicity toward normal liver LO2 cells. Derivative 47 concentration-dependently inhibited the colony formation of MDA-MB-231 cells. NO-releasing assessment indicated that the intracellular NO level was almost positively correlated with the antiproliferative ability. Compound 47, which released the highest amounts of NO, showed the best potency (IC50 = 1.23 μM) against MDA-MB-231 cells. Mechanism research revealed for the first time that 47 blocked the proliferation of MDA-MB-231 cells by activating mitochondrial apoptosis pathway and arresting cell cycle at G2/M phase. Taken together, as a novel scopoletin derivative, 47 exhibited excellent inhibitory effects against malignant cancer cells and lower toxicity on normal cells. Thus, an in-depth evaluation of 47 to explore its complete therapeutic potential for cancer treatment is warranted.
- Chen, Cheng,Chen, Li,Lei, Zhichao,Li, Na,Shi, Zhixian,Sun, Jianbo,Wang, Yujin
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- Escoparone chemical whole synthetic method
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The invention discloses escoparone chemical whole synthetic method, which belongs to the technical field of chemical synthesis, escoparone chemical full-synthetic method is 2, 4, 5 - trimethoxybenzaldehyde de-methyl generating 4 - dihydroxy - 5 - methoxybenzaldehyde; 4 - dihydroxy - 5 - methoxy benzaldehyde with malonic acid to generate the cyclization reaction to produce the 3 - carboxyl scopolamine lactone; 3 - carboxyl scopolamine lactone by microwave auxiliary decarboxylative generating scopolamine lactone; scopolamine lactone by methylation get escoparone, aims to solve the low efficiency of the plant extract, the disadvantage of low yield and the synthetic yield is low, high cost, is not suitable for the industrial application of the shortcomings.
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Paragraph 0032; 0039-0041; 0045; 0052-0054
(2019/05/15)
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- Preparation method of scopoletin
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The invention discloses a preparation method of scopoletin, which comprises the following steps: 1) with 2,4-dihydroxy-5-methoxybenzaldehyde as an initial raw material, adding a solvent and a catalyst, adding a malonic acid compound within a reaction temperature range of 0-300 DEG C, and carrying out a heat preservation reaction for 2-10 hours to obtain a reaction solution, the usage amount of the malonic acid compound being 1-10 equivalents; 2) cooling the reaction solution at a cooling temperature of -10 DEG C to 35 DEG C, wherein a large amount of solids is separated after the reaction solution is cooled, and carrying out reduced pressure suction filtration on the reaction solution from which the large amount of solids are separated out to obtain a crude product of the scopoletin and filtrate; and 3) recrystallizing the crude product of the scopoletin with ethyl acetate to obtain a pure product of the scopoletin. The method has the advantages of high yield, low cost and low pollution.
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Paragraph 0048-0052
(2019/10/04)
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- Synthesis and acaricidal activities of scopoletin phenolic ether derivatives: Qsar, molecular docking study and in silico Adme predictions
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Thirty phenolic ether derivatives of scopoletin modified at the 7-hydroxy position were synthesized, and their structures were confirmed by IR,1H-NMR,13C-NMR, MS and elemental analysis. Preliminary acaricidal activities of these compounds against female adults of Tetranychus cinnabarinus (Boisduval) were evaluated using the slide-dip method. The results indicated that some of these compounds exhibit more pronounced acaricidal activity than scopoletin, especially compounds 32, 20, 28, 27 and 8 which exhibited about 8.41-, 7.32-, 7.23-, 6.76-, and 6.65-fold higher acaricidal potency. Compound 32 possessed the the most promising acaricidal activity and exhibited about 1.45-fold higher acaricidal potency against T. cinnabarinus than propargite. Statistically significant 2D-QSAR model supports the observed acaricidal activities and reveals that polarizability (HATS5p) was the most important parameter controlling bioactivity. 3D-QSAR (CoMFA: q2 = 0.802, r2 = 0.993; CoMSIA: q2 = 0.735, r2 = 0.965) results show that bulky substituents at R4, R1, R2 and R5 (C6, C3, C4, and C7) positions, electron positive groups at R5 (C7) position, hydrophobic groups at R1 (C3) and R2 (C4), H-bond donors groups at R1 (C3) and R4 (C6) will increase their acaricidal activity, which provide a good insight into the molecular features relevant to the acaricidal activity for further designing novel acaricidal agents. Molecular docking demonstrates that these selected derivatives display different bide modes with TcPMCA1 from lead compound and they interact with more key amino acid residues than scopoletin. In silico ADME properties of scopoletin and its phenolic ether derivatives were also analyzed and showed potential to develop as good acaricidal candidates.
- Luo, Jinxiang,Lai, Ting,Guo, Tao,Chen, Fei,Zhang, Linli,Ding, Wei,Zhang, Yongqiang
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- Design, synthesis and cytotoxic activities of scopoletin-isoxazole and scopoletin-pyrazole hybrids
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12 novel scopoletin-isoxazole and scopoletin-pyrazole hybrids were designed, synthesized and their chemical structures were confirmed by HR-MS, IR,1H NMR and13C NMR spectra. The anticancer activities of the newly synthesized compounds were evaluated in vitro against three human cancer cell lines including HCT-116, Hun7 and SW620 by MTT assay. The screening results showed that six compounds (9a, 9c, 9d, 12a, 18b and 18d) exhibited potent cytotoxic activities with IC50values below 20?μM. Besides, we have further evaluated the growth inhibitory activities of six compounds against the human normal tissue cell lines HFL-1. Especially, compound 9d displayed significant anti-proliferative activity with IC50values ranging from 8.76?μM to 9.83?μM and weak cytotoxicity with IC50value of 90.9?μM on normal cells HFL-1, which suggested that isoxazole-based hybrids of scopoletin were an effective chemical modification to improve the anticancer activity of scopoletin.
- Shi, Wei,Hu, Jinglin,Bao, Na,Li, Dongang,Chen, Li,Sun, Jianbo
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supporting information
p. 147 - 151
(2016/12/27)
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- Chemically selective mono-methylation method of coumarin catechol compounds
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The invention provides a chemically selective mono-methylation method of coumarin catechol compounds, and belongs to the field of natural drug synthesis. According to the method, catechol coumarin compounds are added into an organic reaction system in the presence of a proper amount of alkali catalyst, and high selectivity methylation reactions happen between the catechol coumarin compounds and a methylation reagent so as to obtain a mono-methylation product; wherein the mole ratio of the alkali to the catechol coumarin compounds is 1.0-5.0:1; the mole ratio of the methylation reagent to the catechol coumarin compounds is 1.0-2.0:1, the temperature of the reaction system is -20 to 10 DEG C, and the reaction time is 0.5 to 3 hours. The method has the characteristics of simple operation, mild conditions, good selectivity, and high yield, and can be used to prepare mono-methylation products of coumarin catechol compounds with different substituents.
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Paragraph 0027; 0028; 0029; 0030
(2017/05/06)
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- Gastroprotective activity of synthetic coumarins: Role of endogenous prostaglandins, nitric oxide, non-protein sulfhydryls and vanilloid receptors
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Natural or synthetic coumarins showed gastroprotective and antiulcer activity in animal models. In this study, we have synthetized twenty coumarins using classic methods to evaluate their gastroprotective effects on the ethanol/HCl-induced gastric lesion model in mice at 20?mg/kg. Among the coumarins synthetized, compounds 6 and 10 showed the greatest gastroprotective activity being as active as lansoprazole at 20?mg/kg and reducing gastric lesions by 75 and 76%, respectively. Then, in a second experiment, compounds 6 and 10 were re-evaluated in order to understand the possible mode of gastroprotective activity. Regarding coumarin 6, the protective effect was reduced by pre-treatment of the mice with N-ethylmaleimide and l-NAME suggesting that sulfhydryl compounds and endogenous nitric oxide are involved in its gastroprotective activity. While for coumarin 10 the effect was reduced by pre-treatment with indomethacin suggesting that prostaglandins are positively involved in its gastroprotective activity.
- Sepulveda, Beatriz,Quispe, Cristina,Simirgiotis, Mario,Torres-Benítez, Alfredo,Reyes-Ortíz, Johanna,Areche, Carlos,García-Beltrán, Olimpo
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supporting information
p. 5732 - 5735
(2016/11/25)
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- Enzymatic production of oroxylin A and hispidulin using a liverwort flavone 6-O-methyltransferase
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Oroxylin A and hispidulin, compounds which are abundant in both Scutellaria and liverwort species, are important lead compounds for the treatment of ischemic cerebrovascular disease. Their enzymatic synthesis requires an O-methyltransferase able to interact with the related flavonoid's 6-OH group, but such an enzyme has yet to be identified in plants. Here, the gene encoding an O-methyltransferase (designated PaF6OMT) was isolated from the liverwort species Plagiochasma?appendiculatum. A test of alternative substrates revealed that its strongest preferences were baicalein and scutellarein, which were converted into, respectively, oroxylin A and hispidulin. Allowed a sufficient reaction time, the conversion rate of these two substrates was, respectively, 90% and 100%. PaF6OMT offers an enzymatic route to the synthesis of oroxylin A and hispidulin.
- Zhang, Yu-Ying,Xu, Rui-Xue,Gao, Shuai,Cheng, Ai-Xia
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p. 2619 - 2628
(2017/01/14)
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- Synthesis and anti-acetylcholinesterase activity of scopoletin derivatives
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A series of scopoletin derivatives incorporated with the pyridinium moiety was synthesized and evaluated for their acetylcholinesterase (AChE) inhibitory activity by the colorimetric Ellman's method. A 2-fluorobenzylpyridinium derivative was the most potent among the tested compounds, with an IC50 value of 0.215 ± 0.015 μM, which was greatly improved from that of scopoletin. Docking studies revealed that the scopoletin portion of the mentioned compound was bound to the peripheral anionic site of the AChE, whereas the N-benzylpyridinium residue to the catalytic anionic site.
- Khunnawutmanotham, Nisachon,Chimnoi, Nitirat,Saparpakorn, Patchreenart,Techasakul, Supanna
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p. 137 - 145
(2016/03/09)
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- Scopolamine lactone derivative and its preparation method and application
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The invention discloses a scopoletin derivative as well as a preparation method and an application thereof. The general formula of the scopoletin derivative is formula (I), wherein R is selected from C1-4 alkyl and X is selected from a halo substituent. The scopoletin derivative has a remarkable anticoagulation effect and can remarkably prolong the in vitro blood coagulation time. The scopoletin derivative orally taken can quickly enter into blood to have the anticoagulation effect. The onset time and the curative effect of the scopoletin derivative for treating venous thromboembolic diseases are equivalent to those of warfarin and the scopoletin derivative is smaller in dosage and easy to control. The scopoletin derivative has novel medical use of preventing and treating venous thromboembolic diseases and meanwhile provides a novel treatment candidate medicine for patients with venous thromboembolic diseases. The invention further discloses the preparation method of the scopoletin derivative and the application of the scopoletin derivative in preparing anticoagulation medicines.
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- Synthesis, in vitro and in vivo antitumor activity of scopoletin-cinnamic acid hybrids
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A series of hybrids of scopoletin and substituted cinnamic acid were designed, synthesized and evaluated in vitro and in vivo against five human tumor cell lines [MCF-7, MDA-MB-231, A549, HCT-116, and HeLa] with doxorubicin as the positive control. Compounds 17a, 17b, 17c and 17g exhibited potent cytotoxic activity. Especially, compound 17b displayed broad spectrum activity with IC50 values ranging from 0.249 μ1/4M to 0.684 μ1/4M. Moreover, in a preliminary pharmacological study, 17b not only remarkably induced cellular apoptosis, but also clearly induced A549 cells cycle arrest at S phase. In vivo study showed that 17b significantly suppressed tumor growth in a dose-dependent manner without causing the loss of the mean body weight of mice, which was superior to doxorubicin. These preliminary results indicate that 17b is an optimal anti-cancer leading compound and merit further structural modification.
- Li, Linhu,Zhao, Peng,Hu, Jinglin,Liu, Jinhong,Liu, Yan,Wang, Zhiqiang,Xia, Yufeng,Dai, Yue,Chen, Li
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p. 300 - 307
(2015/03/04)
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- Synthesis and biological evaluation of scopoletin derivatives
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A series of new scopoletin derivatives were designed and synthesized. Their anti-proliferative effect was initially evaluated against various human cancer cell lines. Among the tested compounds, A1, A2, and D6 showed significant anti-proliferative activities. Angiogenesis was detected by endothelial cell migration assay and tube formation study. The results showed that A1, A2, and D6 inhibited the vascular endothelial growth factor (VEGF)-stimulated proliferation, migration, and tube formation of human umbilical vein endothelial cells in vitro. Moreover, they inhibited the vessel growth in the chorioallantoic membrane in vivo. This inhibition was correlated with a significant decrease in the VEGF-triggered phosphorylated forms of ERK1/2 and Akt. In summary, these findings strongly suggested that these scopoletin derivatives might be structurally novel angiogenesis inhibitors.
- Cai, Xueting,Yang, Jie,Zhou, Jinpei,Lu, Wuguang,Hu, Chunping,Gu, Zhenhua,Huo, Jiege,Wang, Xiaoning,Cao, Peng
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- Total synthesis of six 3,4-unsubstituted coumarins
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In this article we describe a new methodology for the total synthesis of 3,4-unsubstituted coumarins from commercially available starting materials. Six examples were prepared, including five naturally occurring coumarins-7-hydroxy- 6,8-dimethoxycoumarin (isofraxidin), 7-hydroxy-6-methoxycoumarin (scopoletin), 6,7,8-trimethoxycoumarin, 6,7-dimethoxycoumarin (scoparone), and 7,8-dihydroxycoumarin (daphnetin) and one synthetic coumarin, 7-hydroxy-6-ethoxycoumarin. Moreover, five important o-hydroxybenzaldehyde intermediates were also obtained, namely 2,4-dihydroxy-3,5- dimethoxybenzaldehyde, 2,4-dihydroxy-5-methoxybenzaldehyde, 5-ethoxy-2,4- dihydroxybenzaldehyde, 2-hydroxy-3,4,5-trimethoxybenzaldehyde, and 2-hydroxy-4,5-dimethoxybenzaldehyde. The method developed herein involves just three or four steps and allows for the rapid synthesis of these important molecules in excellent yields. This is the first synthesis of 6,7,8-trimethoxycoumarin and 7-hydroxy-6-ethoxycoumarin.
- Gao, Wenqing,Li, Qingyong,Chen, Jian,Wang, Zhichao,Hua, Changlong
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p. 15613 - 15623
(2014/01/17)
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- Synthesis and antitumor activity of scopoletin derivatives
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Studies have shown that natural product scopoletin has significant pharmacological activities, such as antiarthritic, spasmolytic, antitumoral, antidepressant-like, antifungal, antihyperglycemic and antioxidative. In search of new antitumor agents, twelve scopoletin derivatives were designed and synthesized by a systematic combinatorial chemical approach and their chemical structures were confirmed by MS, IR, 1H NMR spectra and elemental analysis. Preliminary screening against mammary cells HUVEC and MCF-7 indicated that three compounds (5a, 5b, 5e) displayed reasonable antitumor activity with IC50 values below 18 μM whereas scopoletin showed its IC 50 values above 100 7μM. These results clearly indicated that structural modification of scopoletin can greatly increase its antitumor activity in vitro.
- Zhou, Jinpei,Wang, Lei,Wei, Lijuan,Zheng, Yu,Zhang, Huibin,Wang, Yubin,Cao, Peng,Niu, Ao,Wang, Jing,Dai, Yue
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experimental part
p. 397 - 401
(2012/07/28)
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- Synthesis and in vitro antitumor activity of novel scopoletin derivatives
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Twenty scopoletin derivatives were developed by a systematic combinatorial chemical approach and their chemical structures were confirmed by MS, IR, 1H NMR spectra and elemental analysis. Primary screening against mammary (MCF-7 and MDA-MB 231) and colon (HT-29) carcinoma cells indicated that five compounds (8d, 8g, 8j, 11b and 11g) displayed high antitumor potencies with IC50 values below 20 μM whereas scopoletin showed IC50 values above 100 μM. Moreover, the most promising compound 11g was more active than 5-fluorouracil. These results clearly indicated that the modification of the scopoletin structure could greatly increase its antitumor activity in vitro.
- Liu, Wukun,Hua, Jie,Zhou, Jinpei,Zhang, Huibin,Zhu, Haiyang,Cheng, Yanhua,Gust, Ronald
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supporting information; experimental part
p. 5008 - 5012
(2012/08/28)
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- Lamellarins as inhibitors of P-glycoprotein-mediated multidrug resistance in a human colon cancer cell line
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Chemical analysis of a Didemnum sp. (CMB-01656) collected during scientific Scuba operations off Wasp Island, New South Wales, yielded five new lamellarins A1 (1), A2 (2), A3 (3), A4 (4) and A5 (5) and eight known lamellarins C (6), E (7), K (8), M (9), S (10), T (11), X (12) and χ (13). Analysis of a second Didemnum sp. (CMB-02127) collected during scientific trawling operations along the Northern Rottnest Shelf, Western Australia, yielded the new lamellarin A6 (14) and two known lamellarins G (15) and Z (16). Structures were assigned to 1-16 on the basis of detailed spectroscopic analysis with comparison to literature data and authentic samples. Access to this unique library of natural lamellarins (1-16) provided a rare opportunity for structure-activity relationship (SAR) investigations, probing interactions between lamellarins and the ABC transporter efflux pump P-glycoprotein (P-gp) with a view to reversing multidrug resistance in a human colon cancer cell line (SW620 Ad300). These SAR studies, which were expanded to include the permethylated lamellarin derivative (17) and a series of lamellarin-inspired synthetic coumarins (19-24) and isoquinolines (25-26), successfully revealed 17 as a promising new non-cytotoxic P-gp inhibitor pharmacophore. Copyright
- Plisson, Fabien,Huang, Xiao-Cong,Zhang, Hua,Khalil, Zeinab,Capon, Robert J.
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supporting information; experimental part
p. 1616 - 1623
(2012/09/08)
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- New approach for the construction of the coumarin frame and application in the total synthesis of natural products
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A new synthetic approach is described for building the coumarin scaffold through the Lewis acid-promoted cyclization of novel aryl 3-(dimethylamino)prop- 2-enoates 2a - 2f. The latter precursors were prepared via aminomethylenation of the corresponding aryl acetates 4a - 4f with the Bredereck reagent. This approach was used for the synthesis of biologically active natural compounds 1a - 1f, through a three-step procedure starting from the corresponding phenols.
- Jerezano, Alberto,Jimenez, Fabiola,Del Carmen Cruz, Maria,Montiel, Luisa E.,Delgado, Francisco,Tamariz, Joaquin
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p. 185 - 198
(2011/04/17)
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- Part 148 in the series "studies on novel synthetic methodologies:" Selective acetylation of alcohols, phenols and amines and selective deprotection of aromatic acetates using silica-supported phosphomolybdic acid
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An environmentally friendly silica-supported phosphomolybdic acid was found to be a highly efficient catalyst for the selective acetylation of alcohols, phenols and amines in the absence of any solvent and also for the chemoselective deprotection of aromatic acetates under very mild conditions. This method has been used for the protection of the hydroxy groups as well as for the deprotection of the acetates of several naturally occurring bioactive phenolic compounds. The catalyst can be easily recovered and reused.
- Das, Biswanath,Thirupathi, Ponnaboina,Kumar, Rathod Aravind,Laxminarayana, Keetha
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p. 2677 - 2683
(2008/09/19)
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- Synthesis of virgatol and virgatenol, two naturally occurring coumarins from Pterocaulon virgatum (L.) DC, and 7-(2,3-epoxy-3-methylbutoxy)-6- methoxycoumarin, isolated from Conyza obscura DC
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The synthesis of a number of naturally occurring coumarins from Pterocaulon virgatum (L.) and Conyza obscura DC is described for the first time. It concerns the synthesis of 7-(2-hydroxy-3-methoxy-3-methylbutoxy)-6- methoxycoumarin (virgatol, 1), 7-(2-hydroxy-3-methyl-3-butenyloxy)-6- methoxycoumarin (virgatenol, 2) and 7-(2,3-epoxy-3-methylbutoxy)-6- methoxycoumarin (3). In addition, a straightforward synthesis of scopoletin (4) (7-hydroxy-6-methoxycoumarin) is reported and the synthesis of a new coumarin derivative, 6-methoxy-7-(2-oxo-3-methylbutoxy)coumarin (7), is described.
- Demyttenaere, Jan,Vervisch, Stijn,Debenedetti, Silvia,Coussio, Jorge,Maes, Dominick,De Kimpe, Norbert
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p. 1844 - 1848
(2007/10/03)
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- Simple, efficient, and selective deprotection of phenolic methoxymethyl ethers using silica-supported sodium hydrogen sulfate as a heterogeneous catalyst
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A simple and efficient method has been developed for chemoselective deprotection of phenolic methoxymethyl (MOM) ethers using silica-supported sodium hydrogen sulfate as a heterogeneous catalyst. The conversions occur at room temperature, and the yields of the deprotected phenols are excellent. The method is suitable for deprotection of phenolic MOM ethers of multifunctional bioactive natural products.
- Ramesh,Ravindranath,Das, Biswanath
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p. 7101 - 7103
(2007/10/03)
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- Synthesis of 6-methoxy-4H-1-benzopyran-7-ol, a character donating component of the fragrance of Wisteria sinensis
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6-Methoxy-4H-1-benzopyran-7-ol 7, a major impact flavor compound of Wisteria sinensis has been synthesized from 2,4,5-trimethoxybenzaldehyde 1 via scopoletin 3. The synthetic sequence comprised (i) bisdemethylation of 2,4,5-trimethoxybenzaldehyde 1, (ii) Wittig reaction with ethoxycarbonylmethylenetriphenylphosphorane, (iii) hydrogenation on palladium/carbon in glacial acetic acid, (iv) DIBAL-H reduction of the intermediate lactone and (v) dehydration of the lactol with anhydrous oxalic acid.
- Demyttenaere, Jan,Van Syngel, Kris,Peter Markusse,Vervisch, Stijn,Debenedetti, Silvia,De Kimpe, Norbert
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p. 2163 - 2166
(2007/10/03)
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- An improved and large scale synthesis of the natural coumarin scopoletin
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Isovanillin was oxidized with magnesium monoperoxyphthalate to 4-methoxyresorcinol (2) and the latter was reacted with 3-oxo-propionic acid ethylester prepared in situ to give scopoletin (1). These reactions can be achieved in kg scale in high yields.
- Hauer,Ritter,Grotemeier
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p. 737 - 738
(2007/10/03)
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- A FURANOCOUMARIN GLUCOSIDE FROM STEMBARK OF SKIMMIA JAPONICA
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From the stembark of Skimmia japonica the new furanocoumarin glucoside, 2,3-dihydro-9-hydroxy-2--7H-furo -benzopyran-7-one has been isolated along with three known coumarin glucosides.They have been found in female and male plants of the species. Key Word Index: Skimmia japonica ssp. japonica; Rutaceae; coumarin glucosides; structural determination.
- Reisch, Johannes,Achenbach, Stefan H.
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p. 4376 - 4377
(2007/10/02)
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- SECOIRIDOID, COUMARIN AND SECOIRIDOID-COUMARIN GLUCOSIDES FROM FRAXINUS CHINENSIS
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Besides the known glucosides, oleuropein, neooleuropein and cichoriin, a new secoiridoid glucoside, frachinoside, was isolated from leaves of Fraxinus chinensis and its structure elucidated. Key Word Index: Fraxinus chinensis; Oleaceae; secoiridoid glucoside; frachinoside.
- Kuwajima, Hiroshi,Morita, Masami,Takaishi, Kiyokazu,Inoue, Kenichiro,Fujita, Tetsuro,et al.
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p. 1277 - 1280
(2007/10/02)
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- Claisen Rearrangement of Z- and E-4,5-Dimethoxy-2-prenyloxycinnamic Acids: Formation of Scopoletin, Suberosin and 3-Prenylscoparone
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The Z- and E-4,5-dimethoxy-2-prenyloxycinnamic acids (2 and 6), obtained by ring opening of 6,7-dimethoxycoumarin (1; scoparone) under different conditions followed by prenylation, undergo Claisen rearrangement to give scopoletin (3) together with suberosin (4) and 3-prenylscoparone (7), respectively.The steric and sustituent effects have been discussed.
- Koul, S. K.,Taneja, S. C.,Dhar, K. L.
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p. 574 - 575
(2007/10/02)
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- A CHEMICAL STUDY OF PLANTS OF THE MONGOLIAN FLORA LARISIDE - A NEW SCOPOLETIN GLYCOSIDE FROM Salsola laricifolia
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A new coumarin glycoside lariside - C21H26O13, mp 155-156 deg C (from methanol) - has been isolated from the epigeal part of Solsola laricifolia Turcz. et Litw.On the basis of acid hydrolysis and spectral characteristics the structure of lariside has been established as 7-2)-β-D-glucopyranosyloxy>-6-methoxy-2H-1-benzopyran-2-one.
- Narantuyaa, S.,Batsuren, D.,Batirov, E. Kh.,Malikov, V. M.
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p. 267 - 269
(2007/10/02)
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- Chemical Studies on Viburnum awabuki K. KOCH
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From Viburnum awabuki K.KOCH (Caprifoliaceae), four new acetyl glucosides of scopoletin, 2',6'-di-O-acetylscopolin (1), 3',6'-di-O-acetylscopolin (2), 6'-O-acatylscopolin (3) and 2'-O-acetylscopolin (4), and two lupane-type triterpenes, 6α-hydroxylup-20(29)-en-3-on-28-oic acid (6) and its 6β-epimer (7), were isolated.Their structures were elucidated on the basis of physicochemical evidence, including proton and carbon-13 nuclear magnetic resonance spectrometry.Keywords-Viburnum awabuki; coumarin derivative; acetyl glucoside; scopolin; A-value; CD spectrum; lupane-type triterpene; 13C-NMR spectrum
- Kuroyanagi, Masanori,Shiotsu, Michiko,Ebihara, Tsuyoshi,Kawai, Hideaki,Ueno, Akari,Fukushima, Seigo
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p. 4012 - 4017
(2007/10/02)
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- TWO QUASSINOID GLYCOSIDES AND A β-CARBOLINE-1-PROPIONIC ACID FROM HANNOA KLAINEANA
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Key Word Index - Hannoa klaineana; Simaroubaceae; roots; quassinoids; 15-O-β-D-glucopyranosyl-21-hydroxyglaucarubolone; 15-O-α-D-xylofuranosyl(1 -> 6)-β-D-glucopyranosyl-21-hydroxyglaucarubolone; alkaloid; β-carboline-1-propionic acid; coumarin; scopolin. - Among the polar constituents of Hannoa klaineana roots, two new quassinoid glycosides, 15-O-β-D-glucopyranosyl-21-hydroxyglaucarubolone, 15-O-α-D-xylofuranosyl(1 -> 6)-β-D-glucopyranosyl-21-hydroxy-glaucarubolone, an alkaloid, β-carboline-1-propionioc acid and a coumarin glycoside, scopolin were isolated and their structures elucidated.
- Lumonadio Luyengi,Vanhaelen, Maurice
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p. 2387 - 2390
(2007/10/02)
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- Effects of Nutritional Factors on Formation of Scopoletin and Scopolin in Tobacco Tissue Cultures
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At low concentrations, sucrose and phosphate increased the formation of scopoletin and scopolin.Among carbon sources tested, only sucrose was effective in the formation of scopoletin and scopolin.A high concentration of either inorganic nitrogen source or casamino acid increased scopoletin and scopolin formation.L-Phenylalanine as the sole amino acid completely inhibited cell growth and the formation of scopoletin and scopolin, but combining L-phenylalanine and casamino acid remarcably stimulated the formation of scopoletin and scopolin.
- Okazaki, Mitsuo,Hino, Fumitsugu,Nagasawa, Kazuo,Miura, Yoshiharu
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p. 601 - 608
(2007/10/02)
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- COUMARINS OF Haplophyllum obtusifolium. STRUCTURES OF TWO NEW COUMARIN GLYCOSIDES
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Two coumarin glycosides have been isolated from an aqueous ethanolic extract of the epigeal part of Haplophyllum obtusifolium: (I) - C16H16O10, mp 164-166 deg C, D -52.4 deg (dimethylformamide); and (II) - C26H26O12, mp 206-208 deg C, D -110.5 deg (pyridine).It has been established on the basis of chemical transformations and spectral characteristics that (I) has the structure of fraxetin 7-O-β-D-glucopyranoside and (II) that of scopoletin 7-O-(6'-O-feruloyl-β-D-glucopyranoside).
- Batirov, E. Kh.,Matkarimov, A. D.,Malikov, V. M.,Seitmuratov, E.
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p. 654 - 657
(2007/10/02)
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- THE STRUCTURE OF HAPLOPEROSIDE B - AN ACYLATED COUMARIN GLYCOSIDE FROM Haplophyllum perforatum
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By chemical and spectral methods using INDOR the structure of an acylated coumarin glycoside, haploperoside B, isolated from Haplophyllum perforatum has been established as 7--6-methoxycoumarin.
- Yuldashev, M. P.,Batirov, E. Kh.,Malikov, V. M.,Perel'son, M. E.
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p. 518 - 520
(2007/10/02)
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- COUMARIN GLYCOSIDES OF Haplophyllum perforatum
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From the epigeal part of Haplophyllum perforatum we have isolated the coumarins scopoletin (I), scopoletin 7-O-β-D-glucopyranoside (II) and the new coumarin glycoside haploperoside A (III), mp 212-213 deg C, D22 -37 deg (c 0.24, CH3OH).The acid hydrolysis of (III) formed (I) and the monosaccharides D-glucose and L-rhamnose.Partial hydrolysis of (III) with 10percent acetic acid led to (II) and L-rhamnose.On the basis of the results of a study of UV, IR, and PMR spectra, and also periodate oxidation and polarimetric analysis the structure of 6-methoxy-7-1)-β-D-glucopyranosyloxy>coumarin has been established for (III).Details of the IR, UV, PMR, and mass spectra are given.
- Yuldashev, M. P.,Batirov, E. Kh.,Malikov, V. M.
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p. 125 - 128
(2007/10/02)
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