Formation of pyrrolinium derivatives in the bromination reaction of <Emphasis Type=Italic>N</Emphasis>,<Emphasis Type=Italic>N</Emphasis>-dipropargyl ammonium salts

Bromination of ammonium salts containing two propargyl groups afforded bromine-substituted derivatives of pyrrolinium salts. The reactions of piperidinium and morpholinium analogs resulted in spirocyclic ammonium salts.     

Syntheses proceeding from <Emphasis Type=Italic>N</Emphasis>-(oxiran-2-ylmethyl)-<Emphasis Type=Italic>N</Emphasis>-ethylaniline

The preparation of N-(oxiran-2-ylmethyl)-N-ethylaniline was developed. The compound was used in the synthesis of new N-derivatives of aromatic amines containing vicinal aminoalcohol moieties.     

Ultrasound-accelerated one-pot synthesis of <Emphasis Type=Italic>N</Emphasis>-acetyl-2-aryl-1,2-dihydro-4<Emphasis Type=Italic>H</Emphasis>-3,1-benzoxazin-4-ones

The one-pot synthesis of N-acetyl-2-aryl-1,2-dihydro-4H-3,1-benzoxazin-4-one derivatives from the condensation reaction of anthranilic acids with heteroaromatic aldehydes in the presence of excess amount of acetic anhydride has been explored. The reactions proceed smoothly under ultrasound irradiation and without catalyst at 35 − 40 °C to afford the title products in high yields.     

Synthesis and some transformations of <Emphasis Type=Italic>N</Emphasis>,2,2-trimethyltetrahydro-2<Emphasis Type=Italic>H</Emphasis>-pyran-4-amine

Reaction of 2,2-dimethyltetrahydro-2H-pyran-4-one with aqueous methanamine, followed by reduction of the Schiff base thus obtained with sodium tetrahydridoborate gave N,2,2-trimethyltetrahydro-2H-pyran-4-amine which was subjected to cyanoethylation with acrylonitrile. The resulting 3-(2,2-dimethyltetrahydro-2H-pyran-4-ylmethylamino)propanenitrile was reduced with lithium tetrahydridoaluminate to N-(2,2-dimethyltetrahydro-2H-pyran-4-yl)-N-methylpropane-1,3-diamine, and some chemical transformations of the latter were studied.     

Epoxide tethering of polymeric <Emphasis Type=Italic>N</Emphasis>-halamine moieties

Three heterocyclic N-halamine structures containing amine, amide, or both functional groups were immobilized onto cotton fabric through epoxide tethering. The coatings were rendered biocidal upon exposure to dilute household bleach solution. The coatings exhibited superior biocidal functionality with complete inactivation of about 6 logs of Staphylococcus aureus and Escherichia coli O157:H7 within 2–10 min contact time depending on the structure. Moreover, the coatings were quite stable against repeated laundering so that recharging was not even necessary after 50 washing cycles. Stability of the coatings against ultraviolet light exposure was studied with a comparison of the amide- and amine-containing N-halamines.     

Oxidative cyclization of <Emphasis Type=Italic>N</Emphasis>-alkyl-2-arylhydrazonothioacetamides

Oxidative cyclization of N-alkyl-2-arylhydrazono-2-cyanothioacetamides by the action of N-chlorosuccinimide, bromine, or iodine affords 4-cyano-5-imino-1,2,3-thiadiazoles.     

Reactions of 1-bromo-1-nitro-3,3,3-trichloropropene with <Emphasis Type=Italic>O</Emphasis>- and <Emphasis Type=Italic>N</Emphasis>-nucleophiles

Reactions of 1-bromo-1-nitro-3,3,3-trichloropropene with alcohols, benzidine and o-, m-, and p-phenylenediamines was investigated and the reaction conditions were developed. The alkoxylation and amination products and an unusual nitrogen-containing bis-aziridine were obtained; their structures were characterized by the spectral (IR, ¹H, ¹³C NMR, HMQC, and HMBC) methods.     

Diterpenoid acids from <Emphasis Type=Italic>Pinus koraiensis</Emphasis>

Two new diterpenoid acids, pinusenocarp (1) and pinusenoid (2), were isolated from the pine cone of Pinus koraiensis. All the compounds were characterized on the basis of spectral analysis, viz. ¹H NMR, ¹³C NMR, IR, UV, ESI-MS, and elemental analysis.     

Regioselective <Emphasis Type=Italic>N</Emphasis>-alkylation of (2-chloroquinolin-3-yl) methanol with <Emphasis Type=Italic>N</Emphasis>-heterocyclic compounds using the Mitsunobu reagent

The Mitsunobu reaction is a well-established fundamental reaction and has been widely applied in organic synthesis. In this paper, under Mitsunobu conditions dehydration proceeds between (2-chloroquinolin-3-yl)methanol and nitrogen heterocyclic compounds such as quinazolinone, pyrimidone, 2-oxoquinoline in dry THF in the presence of triethylamine, triphenylphosphane and diethyl azodicarboxylate to give the corresponding products. As part of our recent research, we attempted to couple two N-heterocyclic compounds under Mitsunobu reaction conditions to provide efficient building blocks for natural product synthesis.