The zinc-mediated regioselective addition reactions of diethyl bromomalonate and aromatic and aliphatic alkynes were investigated for the synthesis of vinyl malonates. When the vinyl organo-zinc intermediates were reacted with acid chlorides 2H-pyran-2-ones were obtained while the application of oxalyl chloride and an amine led to tetracarbonyl derivatives in a one-pot multi-step reaction seque...

Tetrahydrobenzo[b]pyran derivatives 1 were utilized for the synthesis of several new pyrano[2,3-d]pyrimidine derivatives 2. Compound 2 was obtained in the presence of Ac2O/H2SO4 (as a catalyst) and was confirmed by spectroscopic data such as IR, 1H NMR and 13C NMR. Ab initio calculation was carried out to study geometric optimization, t...

ABSTRACT. Benzoylacetone (1) underwent a series of multi-component reactions with aromatic aldehydes and malononitrile or ethyl cyanoacetate to produce the pyran derivatives 4a-f. The latter compounds reacted yield condensation products 5a-m. On other hand, reaction 4a-f either diazonium salts 6a-c yielded arylhydrazone 7a-i. adehydes cyclohexan-1,3-dione produced 9a-c. Compound 1 Gewald’s elem...

Thiazoles and thiazolyl-pyrazole derivatives have been efficiently synthesized under neat reaction conditions in excellent yields. Condensation of 3-(2-bromoacetyl)-4-hydroxy-6-methyl-2H-pyran-2-one (1), thiosemicarbazide (2) and various carbonyl compounds (3 & 5) gave corresponding thiazole (4) and thiazolylpyrazole derivatives (6) in excellent yields by using Hantzsch-Thiazole synthesis. The ...

A new, simple thermally efficient and solvent-free condensation of 2-amino-3-cyano-6-methyl-4-phenyl-4H-pyran-5-ethylcarboxylate derivatives with coumarin-3-carboxylic acid employing pentafluorophenylammonium triflate (PFPAT) as an inexpensive organocatalyst for the synthesis of a series of ethyl 4,5-dihydro 7-methyl-2-(2-oxo-2H-chromen-3-yl)-4-oxo-5-aryl-3H-chromeno[2,3-d]pyrimidine-6-carboxyl...

the three components one pot synthesis of 2-amino-4h-benzo-[b] -pyran derivatives were obtained in good to excellent yields within short reaction time by condensing dimedone, aldehydes and malanonitrile or ethylcyanoacetate using a catalytic amount of (diacetoxyiodo)benzene as hypervalent iodine in aqueous ethanol under reflux conditions have been discussed. this aqua mediated knoevenagel-cyclo...

Many new cyclized pyran systems with a potential anti-cancer activity were designed and prepared. Pyran showed high reactivity to various chemical reagents. 24 products of the prepared compounds chosen tested in (mM) as respectable anticancer factors. The findings revealed that 3b, 6b, 8 widely effective against three cancer cell lines including A-549 (lung carcinoma), HC-29 (colorectal adenoca...

Chromene is considered a fused pyran ring with benzene ring, which found in many plants and part of important compounds such as anthocyanidins, anthocyanins, catechins, flavanones. These are included under the headings "flavonoids" "iso-flavonoids." well known bioactive molecules wide medicinal uses. According to these pharmacokinetic characteristics, researchers giving more attention this type...

The title compound, C(7)H(14)O(2), is a vicinal diol derived from cyclo-heptane with cis-orientated hydr-oxy groups. The mol-ecules shows no non-crystallographic symmetry. The O-C-C-O torsion angles of both mol-ecules present in the asymmetric unit [-66.4 (2) and -66.9 (2)°] are similar to those in trans-configured cyclo-hexane derivatives (including pyran-oses) as well as rac-trans-cyclo-hepta...