Synthesis and reactions of β-substituted derivatives of furan

1985 ◽  
Vol 50 (9) ◽  
pp. 2077-2083 ◽  
Author(s):  
Adolf Jurášek ◽  
Vladimír Žvak ◽  
Jaroslav Kováč ◽  
Oľga Rajniaková ◽  
Jarmila Štetinová

The 1,4-cycloaddition reaction of 4-phenyl-1,3-oxazole to 2-propinyl benzoate and dimethyl butinedioate afforded the respective 3-furylmethyl benzoate (I) and 3,4-bis(methoxycarbonyl)furan (II). These compounds served for the synthesis of 3-chloromethylfuran and 3,4-bis(chloromethyl)furan, which afforded via Wittig reaction 3-(β-arylvinyl)furans III (aryl = 5-nitro-2-furyl (IIIa), 5-nitro-2-thienyl (IIIb), 1-methyl-4-nitro-2-pyrrolyl (IIIc), and 4-nitrophenyl (IIIe)) and 3,4-bis(β-arylvinyl)furans IV (aryl = 5-nitrofuryl (IVa), 5-nitro-2-thienyl (IVc), and 4-nitrophenyl (IVd)). According to spectral evidence (1H NMR, IR, UV spectra), compound IIIa and IIIb originated as E isomers, whilst the remaining products are a mixture of E and Z isomers; some couples were succeded to separate.

1981 ◽  
Vol 46 (2) ◽  
pp. 515-519 ◽  
Author(s):  
Viera Knoppová ◽  
Adolf Jurášek ◽  
Miloslava Dandárová ◽  
Jaroslav Kováč

Reaction of 4-X-benzyltriphenylphosphonium halides with 2-furaldehyde and subsequent Vilsmeier formylation gave 5-(4-X-styryl)-2-furaldehydes ( X = H, Cl, Br, CN, NO2, CH3, and COOCH3). The UV, IR and 1H-NMR spectra of the prepared substances are discussed and it is demonstrated that the compounds are (E) isomers. The UV spectra of 5-styryl-2-furaldehyde have been compared with those of its benzene analogue.


2021 ◽  
Vol 8 (3) ◽  
pp. 202056
Author(s):  
Md. Kausar Ahmed ◽  
Ajoy Kumer ◽  
Abu Bin Imran

Click reaction is a very fast, high yield with no by-product, biocompatible, tolerant to surrounded medium, and very specific cycloaddition reaction between azides and alkynes to form triazole. They are widely being employed in the synthesis of various polymeric materials. Here, the design, fabrication and characterization of hydrogel prepared using click reaction have been reported. At first, telechelic acetylene precursor for click reaction is prepared from diisocyanatohexane and propargyl alcohol in the presence of triethylamine. The azide derivatives of poly(hydroxyethylmethacrylate), i.e. poly(HEMA), are successfully prepared following two different routes. In route 1, esterification of bromopropionic acid is performed with HEMA monomer using N,N′- dicyclohexylcarbodiimide/4-dimethylaminopyridine (DCC/DMAP) as a catalyst followed by replacing bromide by azide moiety. Free radical polymerization of the fabricated monomer is then performed under N 2 atmosphere using azobisisobutyronitrile (AIBN) as an initiator. In route 2, polymerization of HEMA has been carried out first, then modification of the polymer with azide group via successive steps to obtain azide derivative polymer for click reaction. The hydrogel is prepared by a very fast, highly specific, and simple click reaction between azide derivative polymer and telechelic acetylene precursor using copper as a catalyst. The structures of derivatives of azide-functionalized HEMA, acetylene precursors and hydrogels are confirmed by FTIR and 1 H-NMR spectroscopy. The optimized structure of each precursor is determined, and their chemical and thermodynamic parameters are computationally studied in detail.


1981 ◽  
Vol 36 (12) ◽  
pp. 1607-1611 ◽  
Author(s):  
Hans Berbalk ◽  
Karl Eichinger ◽  
Günter Heisler ◽  
Rupert Bauer

Two reaction ways to 3-phenylacetyl-2-oxo-cholest-5-ene (10) as model compound for similar A-ring derivatives of steroids are investigated. The first way starts from the known 6,6-ethylenedioxy-3-oxo-5α-cholestane (1) which is reacted with phenylethinyl-magnesiumbromide to the mixture of epimeric alkinols. The crude mixture of epimers is dehydrated to 6,6-ethylenedioxy-3-phenylethinyl-5α-cholest-2-ene (2), which gives after epoxidation of the double bond and reaction of the resulting crude epoxide with 95 proz. HCOOH the fully enolic 2,6-dioxo-3-phenylacetyl-5α-cholestane (3). Because of a very low total yield of this approach to 10 this way is not further investigated. A successful reaction way starts from the known 6β-hydroxy-5α-cholestane-3-one (4). 4 is reacted with phenylethinylmagnesiumbromide, the 6β-OH group is benzoylated and the tert. alkinols dehydrated in successive steps without isolation of the non crystalline intermediate pro­ducts to 6β-benzoyloxy-3-phenylethinyl-5α-cholest-2-ene (6). Hydrolysis of 6 yields 6β-hydroxy-3-phenylethinyl-5α-cholest-2-ene (7) which is epoxidated at the double bond and the crude epoxide reacted with 95 proz. HCOOH to 6β-formyloxy-3-phenylacetyl-5α-cholestan-2-one (8). Hydrolysis of the formylgroup in 8 yields 9, which gives by acid cata­lysed dehydratisation the desired model compound 10. The structure of 10 is confirmed by its 1H NMR and UV spectra.


1987 ◽  
Vol 52 (12) ◽  
pp. 2918-2925 ◽  
Author(s):  
Viktor Milata ◽  
Dušan Ilavský

The cyclization of 3-N(4- and 5-benzimidazolyl and benztriazolyl)amino-2-cyano- and 2-ethoxycarbonyl-2-propenoate esters Ia, b-IVa, b under the conditions of the Gould-Jacobs reaction leads to angularly ring-fused substituted imidazo or triazolo[4,5-f] (V, VI) and [4,5-h] (VII, VIII) quinolines, respectively. The esters Vb-VIIIb have been transformed into the corresponding chloroderivatives Vc-VIIIc. 3-N(5-Benzimidazolyl and 5-benztriazolyl)amino-2-cyano-2-propenenitriles are cyclized in the presence of aluminium(III) chloride to give the aminoquinolines Vd, VId. The structure of the products has been characterized by their 1H, 13C NMR, IR, and UV spectra.


1984 ◽  
Vol 49 (1) ◽  
pp. 313-319 ◽  
Author(s):  
Věra Přikrylová ◽  
Petr Sedmera ◽  
Josef V. Jizba ◽  
Jindřich Vokoun ◽  
Helena Lipavská ◽  
...  

Reaction of daunomycinone (I) with alcohols and p-toluenesulfonic acid produces a mixture (~3 : 1) of its (7S)- and (7R)-O-alkyl derivatives II-IX. According to the 1H NMR evidence, the alicyclic ring exists in the 9H8 conformation in (7R)-O-alkyl derivatives, on the contrary to (7S)-epimers and 7-epi-daunomycinone that adopt the 8H9 conformation.


2019 ◽  
Vol 23 (11n12) ◽  
pp. 1576-1586 ◽  
Author(s):  
Sara Pfister ◽  
Luca Sauser ◽  
Ilche Gjuroski ◽  
Julien Furrer ◽  
Martina Vermathen

The encapsulation of five derivatives of chlorin e6 with different hydrophobicity and aggregation properties into a series of five poloxamer-type triblock copolymer micelles (BCMs) with varying numbers of polyethylene and polypropylene glycol (PEG, PPG) units was monitored using 1H NMR spectroscopy. NMR chemical shift and line shape analysis, as well as dynamic methods including diffusion ordered spectroscopy (DOSY) and T1 and T2 relaxation time measurements of the chlorin and the polymer resonances, proved useful to assess the chlorin–BCM compatibility. The poloxamers had high capability to break up aggregates formed by chlorins up to intermediate hydrophobicity. Physically entrapped chlorins were always localized in the BCM core region. The loading capacity correlated with chlorin polarity for all poloxamers among which those with the lowest number of PPG units were most efficient. DOSY data revealed that relatively weakly aggregating chlorins partition between the aqueous bulk and micellar environment whereas more hydrophobic chlorins are well retained in the BCM core region, rendering these systems more stable. T1 and T2 relaxation time measurements indicated that motional freedom in the BCM core region contributes to encapsulation efficiency. The BCM corona dynamics were rather insensitive towards chlorin entrapment except for the poloxamers with short PEG chains. The presented data demonstrate that 1H NMR spectroscopy is a powerful complementary tool for probing the compatibility of porphyrinic compounds with polymeric carriers such as poloxamer BCMs, which is a prerequisite in the development of stable and highly efficient drug delivery systems suitable for medical applications like photodynamic therapy of tumors.


2012 ◽  
Vol 77 (1) ◽  
pp. 17-26 ◽  
Author(s):  
Ritu Sharma ◽  
Pushkal Samadhiya ◽  
Savitri Srivastava ◽  
Santosh Srivastava

A new series of N-[3-(10H-phenothiazinyl)-propyl]-2-(substituted phenyl)-4-oxo-5-( substituted benzylidene)-1,3-thiazolidine-carboxamide, 5(as) have been synthesized. The cycloaddition reaction of thioglycolic acid with N-[3-(10H-phenothiazinyl)-propyl]-N?-[(substituted phenyl)-methylidene]- urea, 3(a-s) in the presence of anhydrous ZnCl2 afforded new heterocyclic compounds N-[3-(10H-phenothiazinyl)-propyl]-2-(substituted phenyl)-4-oxo- 1,3-thiazolidine-carboxamide, 4(a-s). The later product on treatment with several selected substituted aromatic aldehydes in the presence of C2H5ONa undergoes Knoevenagel reaction to yield 5(a-s). The structure of compounds 1, 2, 3(a-s), 4(a-s) and 5(a-s) were confirmed by IR, 1H NMR, 13C NMR, Fmass and chemical analysis. All above compounds were screened for their antimicrobial activity against some selected bacteria and fungi and for antituberculosis activity compounds have been screened against the bacterium M. tuberculosis.


2005 ◽  
Vol 2005 (10) ◽  
pp. 640-642 ◽  
Author(s):  
Ying Liu ◽  
Liang Zhao ◽  
Liang Liu ◽  
Lin-Yi Wei ◽  
Lu-Hua Lai

Amino acid derivatives of a modified indole-3-acetic acid have been synthesised. Fourteen new dipeptide-like compounds 3–4 were obtained and their structures were elucidated based on the IR, 1H NMR, MS spectra.


2020 ◽  
Author(s):  
Lifang Guo ◽  
Benshan Xu ◽  
Zirui Wan ◽  
Lulu Ren ◽  
Jie Zhang ◽  
...  

Abstract Background: A series of aryl-piperazine derivatives of 1,7,8,9-tetrachloro-10,10-dimethoxy-4-azatricyclo [5.2.1.0 2,6 ] dec-8-ene-3,5-dione were synthesized. The chemical structures of the desired compounds were identified by 1 H NMR, ESI-MS and elementary analytical. The anti-cancer and anti-angiogenesis activities of the newly synthesized compounds were evaluated by proliferation and migration assays, respectively. Results: The screening results demonstrated that compounds 2 and 5 showed potent anti-tumor activity (IC 50 values ranging from 7.1 to 15.9μM) with low cytotoxic activities (IC 50 > 79.3μM). Although compound 5 showed little effects on endothelia proliferation (IC 50 =65.3μM), it indeed significantly abrogated endothelia cell migration (IC 50 =6.7μM). Conclusions: This work may impart new direction for the investigations of aryl-piperazine derivatives and lead to the development of potent novel anti-tumor and anti-angiogenesis agents.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Neetika Singh ◽  
Mohd. Arish ◽  
Prabhat Kumar ◽  
Abdur Rub ◽  
Ufana Riaz

AbstractTo study the effect of insertion of azobenzene moiety on the spectral, morphological and fluorescence properties of conventional conducting polymers, the present work reports ultrasound-assisted polymerization of azobenzene with aniline, 1-naphthylamine, luminol and o-phenylenediamine. The chemical structure and polymerization was established via Fourier transform infrared (FTIR) spectroscopy, nuclear magnetic resonance (1H-NMR) spectroscopy, while the electronic properties were explored via ultraviolet-visible (UV-vis) spectroscopy. Theoretical IR and UV spectra were computed using DFT/B3LYP method with 6–311G basis set while theoretical 1H-NMR spectra was obtained by gauge independent atomic orbital (GIAO) method. The theoretically computed spectra were found to be in close agreement with the experimental findings confirming the chemical as well as electronic structure of the synthesized polymers. Morphology was investigated by X-ray diffraction and transmission electron microscopy studies. Fluorescence studies revealed emission ranging between 530–570 nm. The polymers also revealed high singlet oxygen (1O2) generation characteristics. In-vitro antileishmanial efficacy as well as live cell imaging investigations reflected the potential application of these polymers in the treatment of leishmaniasis and its diagnosis.


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