scholarly journals A semisynthesis of 3'-O-ethyl-5,6-dihydrospinosyn J based on the spinosyn A aglycone

2017 ◽  
Vol 13 ◽  
pp. 2603-2609 ◽  
Author(s):  
Kai Zhang ◽  
Shenglan Liu ◽  
Anjun Liu ◽  
Hongxin Chai ◽  
Jiarong Li ◽  
...  
Keyword(s):  
Double Bond ◽  
Chemical Synthesis ◽  
Minor Component ◽  
Food Storage ◽  
Selective Protection ◽  
H Nmr ◽  
High Yields ◽  
Agriculture And Food ◽  
Hydrolysis Of ◽  
C Nmr

Spinetoram, a mixture of 3'-O-ethyl-5,6-dihydrospinosyn J (XDE-175-J, major component) and 3'-O-ethylspinosyn L (XDE-175-L, minor component), is a novel kind of green and efficient insecticide with a broad range of action against various insects. Nowadays, spinetoram is widely used in agriculture and food storage. This work reports a 7-step semisynthesis of 3'-O-ethyl-5,6-dihydrospinosyn J from spinosyn A aglycone. The C9–OH and C17–OH of the aglycone are successively connected to 3-O-ethyl-2,4-di-O-methylrhamnose and D-forosamine after selective protection and deprotection steps. Then, with 10% Pd/C as catalyst, the 5,6-double bond of the macrolide was selectively reduced to afford 3'-O-ethyl-5,6-dihydrospinosyn J. In addition, the 3-O-ethyl-2,4-di-O-methylrhamnose is synthesized from rhamnose which is available commercially, while the D-forosamine and aglycone are obtained via the hydrolysis of spinosyn A. High yields were obtained in each step, and all intermediates in the synthesis were characterized by 1H NMR, 13C NMR and MS techniques. This study can be helpful for developing an efficient chemical synthesis of spinetoram, and it also offers opportunities to synthesize spinosyn analogues and rhamnose derivatives.

Ultrasound-assisted aqua-mediated synthesis of multi-substituted tetrahydropyridine-3-carboxylates using N-carboxymethyl-3-pyridinium hydrogensulfate ([N-CH2CO2H-3-pic]+HSO4−) as a new efficient ionic liquid catalyst

2021 ◽  
Vol 3 (6) ◽  
Author(s):  
Kobra Nikoofar ◽  
Fatemeh Shahriyari
Keyword(s):  
Ionic Liquid ◽  
Reaction Times ◽  
Aromatic Aldehydes ◽  
Environmentally Benign ◽  
H Nmr ◽  
Sonic Waves ◽  
Ft Ir ◽  
High Yields ◽  
Work Up ◽  
C Nmr

AbstractA simple, straightforward, and ultrasound-promoted method for the preparation of some highly functionalized tetrahydropyridines reported via pseudo five-component reaction of (hetero)aromatic aldehydes, different anilines, and alkyl acetoacetates in the presence of [N-CH2CO2H-3-pic]+HSO4−, as a novel ionic liquid, in green aqueous medium. The IL was synthesized utilizing simple and easily-handled substrates and characterized by FT-IR, 1H NMR, 13C NMR, GC-MASS, FESEM, EDX, and TGA/DTG techniques. The procedure contains some highlighted aspects which are: (a) performing the MCR in the presence of aqua and sonic waves, as two main important and environmentally benign indexes in green and economic chemistry, (b) high yields of products within short reaction times, (c) convenient work-up procedure, (d) preparing the new IL via simple substrates and procedure.

Cardenolide aus Ornithogalum nutans (2 n = 28), 1. Mitteilung / Cardenolides from Ornithogalum nutans (2 n = 28), Part

1992 ◽  
Vol 47 (10) ◽  
pp. 1444-1458 ◽  
Author(s):  
Roland Ferth ◽  
Andreas Baumann ◽  
Wolfgang Robien ◽  
Brigitte Kopp
Keyword(s):  
Acid Hydrolysis ◽  
Column Chromatography ◽  
Structure Elucidation ◽  
European Species ◽  
H Nmr ◽  
First Time ◽  
Hydrolysis Of ◽  
C Nmr

From leaves and bulbs of Ornithogalum nutans L. (2 n = 28), seventeen cardenolides were isolated by column chromatography, DCCC and TLC. The structure elucidation was performed by means of 1H NMR, 13C NMR, HH-Cosy, HC-Cosy and FAB-MS studies and identification of the sugar moieties by GLC after acid hydrolysis of the cardenolides. Sugar compounds were identified as digitoxose, 3-acetyl-digitoxose, 2-deoxy-allose, 6-deoxy-allose, rhamnose, xylose and apiose. Glycosides of 7β,15β, 16 α-trihydroxy-uzarigenin, 8β,16 α-dihy-droxy, 15-oxo-uzarigenin, 3 β, 11β-dihydroxy, 12-oxo, 18-nor-5 α-card-13-enolid, 11 α-hydroxygitoxigenin, 12-oxo,8, 14β-epoxy-uzarigenin, 8β-hydroxy, 15-oxo-uzarigenin and 12β-hydroxy-oleandrigenin are described for the first time, the presence of oleandrigenin-glycosides in the genus Ornithogalum was not known until now. Ornithogalum nutans L. shows a different cardenolide pattern from the second European species of the section Myogalum (LINK) PETERM. - Ornithogalum boucheanum (KUNTH) ASCHERS.

Synthesis and Biological Activities of Some Schiff's Bases from 4-amino-3-(3-hydroxybutyl)-1H-1, 2, 4-triazole-5-thione

2009 ◽  
Vol 2009 (4) ◽  
pp. 208-211 ◽  
Author(s):  
Jing Zhang ◽  
Lixue Zhang ◽  
Xinxiang Lei ◽  
Changfeng Zhou ◽  
Xiaodan Fu ◽  
...  
Keyword(s):  
Plant Growth ◽  
Elemental Analysis ◽  
Mass Concentration ◽  
Biological Activities ◽  
Schiff’S Bases ◽  
H Nmr ◽  
Schiff's Bases ◽  
High Yields ◽  
C Nmr ◽  
Growth Regulating Activity

Sixteen novel Schiff's bases have been synthesised in high yields from 4-amino-3-(3-hydroxybutyl)-1 H-1, 2, 4-triazole-5-thione. All the newly synthesised compounds have been characterised by elemental analysis, IR, 1H NMR, 13C NMR and MS. Plant growth-regulating activity tests showed that most compounds have remarkable effects on the growth of wheat and radish at a mass concentration of 50μg mL−1.

scholarly journals Synthesis and Spectroscopic Characterization of Some New Biological Active Azo–Pyrazoline Derivatives

2012 ◽  
Vol 9 (3) ◽  
pp. 1613-1622 ◽  
Author(s):  
Farouq E. Hawaiz ◽  
Mohammad K. Samad
Keyword(s):  
Addition Reaction ◽  
Coupling Reaction ◽  
Spectroscopic Characterization ◽  
Hydroxyl Group ◽  
Significant Activity ◽  
H Nmr ◽  
Ft Ir ◽  
High Yields ◽  
C Nmr

A number of 3-[4-(benzyloxy)-3-(2-Chlorophenylazo)-phenyl]-5-(substituted-phenyl)-1-substituted-2-pyrazolines( 4a-j) and (5a-j) have been synthesized by diazotization of 2-chloroaniline and its coupling reaction with 4-hydroxy acetophenone, followed by benzyloxation of the hydroxyl group to give the substrate [4-benzyloxy-3-(2-chlorophenylazo)-acetophenone (1)].The prepared starting material (1) has been reacted with different substituted benzaldehydes to give a new series of chalcone derivatives 1-[(4-benzyloxy)-3-(2-chloro-phenylazo)-phenyl]-3-(substituted phenyl)-2-propen-1-one (3a-j), in high yields and in a few minutes, and the later compounds were treated with hydrazine hydrate according to Michael addition reaction to afford a new biolological active target compounds (4a-j) and (5a-j). Furthermore, The structures of the newly synthesized compounds were confirmed by FT-IR,13C-NMR,13C-DEPT &1H-NMR spectral data. The chalcone and pyrazoline derivatives were evaluated for their anti bacterial activity againstEscherichia colias gram negative andStaphylococcus aureusas gram positive, the results showed significant activity against both types of bacteria.

On the chemistry and high field nuclear magnetic resonance spectroscopy of rapamycin

1980 ◽  
Vol 58 (6) ◽  
pp. 579-590 ◽  
Author(s):  
John A. Findlay ◽  
Lajos Radics
Keyword(s):  
High Field ◽  
Nmr Spectra ◽  
Resonance Spectroscopy ◽  
X Ray ◽  
Conformational Isomers ◽  
H Nmr ◽  
Neutral Compounds ◽  
Complete Assignment ◽  
Hydrolysis Of ◽  
C Nmr

Base catalysed hydrolysis of rapamycin (C51H79NO13) affords six neutral compounds identified by chemical and spectroscopic means as 2a, 3b, 3d, 5, 2,4-dimethylphenol, and L(−)-piperidine-2-carboxylic acid 6, and whose generation has been plausibly rationalized. These findings as well as detailed analyses of 13C nmr and 1H nmr spectra provide independent corroboration of the X-ray derived rapamycin crystal structure 1. Structurally homogeneous in the solid state, rapamycin is found to occur in solutions as a mixture of two conformational isomers (approximately 4:1). Through nearly complete assignment of the high field 1H (400 MHz) and 13C (100.6 MHz) nmr spectra, the isomerism is shown to be associated with trans–cis rotation of an amidic bond within the 31-membered macrolide ring. The predominant form corresponds to the conformer portrayed by X-ray analysis.

scholarly journals Synthesis and Characterization of Novel 1,3-Thiazole and 2-Amino-1,3,4-Thiadiazole Derivatives

2014 ◽  
Vol 33 (2) ◽  
pp. 189 ◽  
Author(s):  
Mustafa Er ◽  
Ayşe Şahin ◽  
Hakan Tahtacı
Keyword(s):  
Biological Activities ◽  
High Yield ◽  
Synthesis And Characterization ◽  
Hantzsch Reaction ◽  
H Nmr ◽  
Thiadiazole Derivatives ◽  
High Yields ◽  
Mass Spectrometric Techniques ◽  
C Nmr

<p>Thiosemicarbazone derivatives <strong>3a–e</strong> were synthesized by the reaction of various aldehydes<strong> 1a–e</strong> with 4-methyl thiosemicarbazide <strong>2</strong> in 78% to 90% yield. Then, the thiazole moieties of the target materials <strong>5a–e</strong> were obtained in high yields (71–93%) using the Hantzsch reaction utilizing thiosemicarbazone derivatives <strong>3a–e</strong> with ethyl-2-chloroacetoacetic ester. The substituted nitrile derivatives <strong>7a–e</strong> were obtained in moderate to high yield (58–84%) from the reaction of compounds <strong>5a–e</strong> with chloroacetonitrile by the nucleophilic aliphatic substitution reaction in the presence of anhydrous potassium carbonate. Finally, substituted 2-amino-1,3,4-thiadiazole compounds <strong>9a–e</strong> were obtained in moderate to good yields (51–62%) from the reaction of thiosemicarbazide with substituted nitrile derivatives <strong>7a–e</strong>. As a result, compounds that all share a high disposition for biological activities were obtained. The structures of the newly synthesized compounds were confirmed by IR, <sup>1</sup>H NMR, <sup>13</sup>C NMR, elemental analysis, and mass spectrometric techniques.</p>

scholarly journals TRANSFORMATION OF ETHYL-P-METHOXYCINNAMATE TO P –METHOXYCINNAMIC ACID FROM KENCUR (Kaempheria galanga L.) AND THEIR ANTIBACTERIAL ACTIVITY

2017 ◽  
Vol 13 (2) ◽  
pp. 176
Author(s):  
Muhamad Salman Fareza ◽  
Rehana Rehana ◽  
Nuryanti Nuryanti ◽  
Didin Mujahidin
Keyword(s):  
Antibacterial Activity ◽  
Antibacterial Properties ◽  
Separation And Purification ◽  
E Coli ◽  
H Nmr ◽  
Alkaline Conditions ◽  
Methoxycinnamic Acid ◽  
Vacuum Liquid Chromatography ◽  
Hydrolysis Of ◽  
C Nmr

This study aimed to evaluate the antibacterial properties of ethyl-<em>p</em>-methoxycinnamate and <em>p</em>-methoxycinnamate acid from Kaempheria galanga L. Ethyl-<em>p</em>-methoxycinnamate was isolated from the <em>n</em>-hexane rhizome extract of <em>Kaempheria galanga L</em>. Separation and purification of this compound was carried out with vacuum liquid chromatography and column chromatography. Hydrolysis of ethyl-<em>p</em>-methoxycinnamic under alkaline conditions obtained <em>p</em>-methoxycinnamic acid with a good yield of 85 %. The structure of the compounds were charactrized with IR, NMR spectrophotometer (<sup>1</sup>H-NMR and <sup>13</sup>C-NMR) and mass spectrophotometer. The antibacterial properties of the compounds were evaluated using microdilution methods against <em>B. cereus</em> ATCC 11778, <em>L. monocytogenes</em> ATCC 7644, <em>E. coli</em> ATCC 25922, <em>S. enterica sv Typhimurium</em> ATCC 14028, and <em>E. aerogenes</em> ATCC 13048. The compounds showed weak antibacterial properties. Only ethyl <em>p</em>-methoxycinnamate showed the strongest antibacterial activity, especially against <em>B. cereus</em> ATCC 11778 bacteria with MIC values of 62.5 mg /mL. The change of the functional groups provided no significant impact on the antibacterial activity.

Synthesis of new 3H-chromeno[2,3-d]pyrimidine-4,6(5H,7H)-diones via the tandem intramolecular Pinner/Dimroth rearrangement

2018 ◽  
Vol 24 (1) ◽  
pp. 31-35 ◽  
Author(s):  
Nasrin Karimi ◽  
Abolghasem Davoodnia ◽  
Mehdi Pordel
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Proton Nuclear Magnetic Resonance ◽  
Phosphoryl Chloride ◽  
Dimroth Rearrangement ◽  
H Nmr ◽  
High Yields ◽  
Aliphatic Carboxylic Acids ◽  
C Nmr ◽  
Nuclear Magnetic

Abstract The reaction of 2-amino-4-aryl-7,7-dimethyl-5-oxo-5,6,7,8-tetrahydro-4H-chromene-3-carbonitriles with excess aliphatic carboxylic acids in the presence of phosphoryl chloride (POCl3) afforded new 2-alkyl-5-aryl-8,8-dimethyl-8,9-dihydro-3H-chromeno[2,3-d]pyrimidine-4,6(5H,7H)-diones in high yields. The suggested mechanism involves a tandem intramolecular Pinner/Dimroth rearrangement. The synthesized compounds were characterized by infrared (IR), proton nuclear magnetic resonance (1H NMR), carbon-13 nuclear magnetic resonance (13C NMR) and elemental analysis.

scholarly journals Tyrosinase enzyme mediated: Synthesis and larvicidal activity of 1,5-diphenyl pent-4-en-1-one derivatives against Culex quinquefasciatus and investigation of Ichthyotoxicity against O. mossambicus

2021 ◽  
Author(s):  
SathishKumar Chidambaram ◽  
Daoud Ali ◽  
Saud Alarifi ◽  
Surendra Kumar Radhakrishnan ◽  
Idhayadhulla Akbar
Keyword(s):  
Larvicidal Activity ◽  
Culex Quinquefasciatus ◽  
Oreochromis Mossambicus ◽  
Docking Studies ◽  
Reaction Conditions ◽  
Mass Spectral ◽  
H Nmr ◽  
Tyrosinase Enzyme ◽  
High Yields ◽  
C Nmr

Abstract Larvicidal activity of 1,5-diphenylpent-4-en-1-one derivatives were synthesized via grindstone method, tyrosinase enzyme used as a catalyst of this process. This method offers high yields with mild reaction conditions. Synthesized compounds were conformed from FTIR, 1H NMR, 13C NMR, mass spectral and elemental analysis. In this study, a total of 17 compounds (1a–1q) were synthesized, and their larvicidal and antifeedant activities were evaluated. Compound 1i (1-(5-oxo-1,5-diphenylpent-1-en-3-yl)-3-(3-phenylallylidene)thiourea) was extremely active (LD50: 12.09 µg/mL) against Culex quinquefasciatus compared with temephos and permethrin, whereas compounds 1i at 100 µg/mL generated 0% mortality within 24h against Oreochromis mossambicus in an antifeedant screening, and Ichthyotoxicity was determined as the death ratio (%) at 24 h. The compounds 1a, 1e, 1f, 1j, and 1k were found to be highly toxic whereas the 1i was not toxic in antifeedant screening. Therefore, 1i was found to have a high larvicidal activity against C. quinquefasciatus, and was non-toxic to non-target aquatic species. Molecular docking studies also supported the finding that 1i is a potent larvicide with more binding energy than the control (-10.0 vs. -7.6 Kcal/mol) in the 3OGN protein. The lead molecule is very important to larvicidal properties and insecticides.

A contribution to peroxy acid oxidation of α,β-unsaturated ketones and linearly conjugated dienones: Reactions in the cholestane series

1988 ◽  
Vol 53 (7) ◽  
pp. 1549-1567 ◽  
Author(s):  
Václav Černý ◽  
Miloš Buděšínský ◽  
Miloš Ryba ◽  
František Tureček
Keyword(s):  
Double Bond ◽  
Carbonyl Group ◽  
Acid Oxidation ◽  
Peroxy Acid ◽  
Unsaturated Ketones ◽  
H Nmr ◽  
Nmr Data ◽  
Epoxy Ketones ◽  
C Nmr

Oxidation with 3-chloroperoxybenzoic acid of s-cis α,β-unsaturated ketones IX, XI and s-trans types X, XII was compared. The s-cis ketones show higher reactivity and furnish a higher yield of the corresponding α,β-epoxy ketones than the s-trans ketones. Products of the Baeyer-Villiger reaction are formed only in low yield. The dienone VI is oxidized predominantly to VII thus violating the rule that linear conjugated dienones are epoxidized at the double bond more distant from the carbonyl group; this result is in accord with the behaviour of s-cis α,β-unsaturated ketones. 1H NMR and 13C NMR data of the starting compounds and of the products are reported.

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