Pyrrolizine-1,3-dione 4 was made by oxidation of the alcohol 2 using pyridinium chlorochromate. The dione 4 shows ketone properties (e.g. formation of DNP derivative 11) and, in common with other pyrrolizinones, the lactam unit is readily ring-opened by methanol under basic conditions. The active methylene unit of 4 couples readily with diazonium salts to provide the hydrazone 15 whose structur...

The regioselective three-component condensation of azomethine ylides derived from isatins and α-amino acids with acrylamides or aroylacrylic acids as dipolarophiles has been realized through a one-pot 1,3-dipolar cycloaddition protocol. Decarboxylation of 2'-aroyl-2-oxo-1,1',2,2',5',6',7',7a'-octahydrospiro[indole-3,3'-pyrrolizine]-1'-carboxylic acids is accompanied by cyclative rearrangement w...

In the title compound, C27H28N2O3, each of the pyrrolidine rings adopts a twisted conformation, as does the cyclo-pentane ring. The indane ring has an r.m.s deviation of 0.0693 Å. The dihedral angle between the mean plane of the pyrrolizine ring and indane system is 82.58 (1)°. The piperidine ring has the methyl substituent in an equatorial position and adopts a twisted chair conformation. The ...

Abstract: Novel ether thionocarbamates, O-butoxy isopropyl-N-ethoxycarbonyl thionocarbamate (BIPECTC) and O-(2-butoxy-1-methylethoxy) isopropyl-N-ethoxycarbonyl thionocarbamate (BMIPECTC), were synthesized in this study. Their collecting efficiencies in the flotation of chalcopyrite were investigated using flotation tests, adsorption measurements, ultraviolet spectra (UV) and Fourier transform-...

A library of original and shelf-stable reagents, source the (ethoxycarbonyl)difluoromethylthio group, is reported. These reagents are applied to functionalization a large panel aldehydes via transition metal-free protocol under mild reaction conditions. This approach offers an efficient access valuable difluoromethylthioester derivatives.

In the title compound, C(29)H(26)N(2)O(2), one of the pyrrolidine rings in the pyrrolizine system is disordered, with site occupancies of ca 0.55 and 0.45. Both components of the disordered pyrrolidine ring adopt envelope conformations, whereas the other pyrrolidine ring adopts a twist conformation. The mol-ecules are linked into centrosymmetric dimers by N-H⋯O hydrogen bonds and the dimers are...

The inhibitory effect of nine phenylcarbamates with various substituents was studied. For this purpose, electrochemical sensors were applied under two different conditions: if an enzyme was present in the solution or if the enzyme was immobilized onto the electrode surface. In both cases, 3-[(ethoxycarbonyl)amino]phenyl (4-chlorophenyl)carbamate was found as the most effective inhibitor for but...

In the title compound, C(24)H(21)ClN(4)O(2)S, the two adjacent spiro junctions link an almost planar (r.m.s. deviation = 0.017 Å) 2-oxindole ring, a hexa-hydro-1H-pyrrolizine ring and a tetra-hydro-imidazo[2,1-b]thia-zole ring. In the crystal, inversion dimers linked by pairs of N-H⋯N hydrogen bonds occur, generating an R(2) (2)(16) loop.

The title compound, C(9)H(11)NO(3), was prepared by an Aldol reaction of 2,3-dihydro-1H-pyrrolizin-1-one with formaldehyde. The asymmetric unit contains six mol-ecules. The pyrrolizine ring system in each mol-ecule is planar, the maximum atomic deviation being 0.066 (2) Å. In the crystal structure, mol-ecules are liked together by an extensive O-H⋯O hydrogen-bonding network.