Alex Yanovsky

Methyl 3-[3-(ethoxy­carbon­yl)thio­ureido]-1H-pyrazole-5-carboxyl­ate

The title compound, C9H12N4O4S, was proven to be the product of the reaction of methyl 5-amino-1H-pyrazole-3-carboxylate with ethyl isothiocyanatocarbonate. All non-H atoms of the molecule are planar, the mean deviation from the least squares plane being 0.048 Å. The intramolecular N—H⋯O bond involving the NH-group, which links the thiourea and pyrazole fragments, closes a six-membered pseudo-heterocyclic ring, and two more hydrogen bonds (N—H⋯O with the participation of the pyrazole NH group and N—H⋯S involving the second thiourea NH group) link the molecules into infinite chains running along [10].

(R)-N-Methyl-4-[2-(methyl-sulfan-yl)pyrimidin-4-yl]-1-(tetra-hydro-furan-3-yl)-1H-pyrazol-5-amine.

The chiral center at the substituted atom of the tetrahydrofuranyl ring in the title compound, C13H17N5OS, has an R configuration. The methylsulfanylpyrimidine group and the pyrazole ring are almost coplanar [the maximum deviation from this plane is 0.070 (4) Å], the N—Me substituent being displaced from the methylsulfanylpyrimidine-pyrazole plane by 0.880 (4) Å. The secondary amine group participates in an intramolecular hydrogen bond with the pyrimidine N atom in position 3.

(3aS,7aS)-5-[(S)-3,3,3-Trifluoro-2-meth-oxy-2-phenyl-propano-yl]-2,3,4,5,6,7-hexa-hydro-1H-pyrrolo[3,4-c]pyridin-3(2H)-one monohydrate.

rac-Benzyl 3-oxohexahydro-1H-pyrrolo[3,4-c]pyridine-5(6H)-carboxylate was separated by chiral chromatography, and one of the enantiomers ([α]22 D = +10°) was hydrogenated in the presence of Pd/C in methanol, producing octahydro-3H-pyrrolo[3,4-c]pyridin-3-one. The latter was reacted with (2R)-3,3,3-trifluoro-2-methoxy-2-phenylpropanoyl chloride [(R)-(−)-Mosher acid chloride], giving rise to the title compound, C17H19F3N2O3·H2O. The present structure established the absolute configuration of the pyrrolopiperidine fragment based on the known configuration of the (R)-Mosher acid chloride. The piperidine ring has a somewhat distorted chair conformation and is cis-fused with the five-membered envelope-shaped ring; the plane of the exocyclic amide bond is approximately orthogonal to the plane of the phenyl ring, making a dihedral angle of 82.31 (3)°. The water molecule acts as an acceptor to the proton of the amino group in an N—H⋯O interaction, and as a double proton donor in O—H⋯O hydrogen bonds, generating infinite bands along the a axis.

2-Morpholino-4-oxo-4,5-dihydro-thio-phene-3-carbonitrile.

The title compound, C9H10N2O2S, was obtained from the treatment of ethyl 4-cyano-3-hydroxy-5-morpholinothiophene-2-carboxylate with concentrated HCl. The mean plane of the essentially planar dihydrothiophene ring is almost orthogonal to the mirror plane of the N-morpholine substituent, making a dihedral angle of 87.2 (2)°.

RacemicN-methyl-4-[2-(methylsulfanyl)pyrimidin-4-yl]-1-(tetrahydrofuran-3-yl)-1H-pyrazol-5-amine

The title compound, C13H17N5OS, was obtained by cycloaddition of 2-[2-(methylsulfanyl)pyrimidin-4-yl]-3-oxopropanenitrile with (tetrahydrofuran-3-yl)hydrazine dihydrochloride and subsequent N-methylation of 4-[2-(methylsulfanyl)pyrimidin-4-yl]-1-(tetrahydrofuran-2-yl)-1H-pyrazol-5-amine with methyl iodide. The two molecules in the asymmetric unit have opposite absolute configurations and are related by a noncrystallographic inversion center. Both feature intramolecular N—H⋯N hydrogen bonds. The geometry of the molecules is similar to that observed in the structure of a single enantiomer of the title compound.

trans-4-(2-Amino-5-bromo-6-methyl­pyrimidin-4-ylamino)-1-methyl­cyclo­hexa­nol

The title compound, C12H19BrN4O, represents the minor component of the two products obtained in a series of transformations involving the Grignard reaction of tert-butoxycarbonyl-protected 4-aminocyclohexanone with MeMgBr, and subsequent interaction of the obtained amino-substituted cyclohexanol with 4-chloro-6-methylpyrimidin-2-amine followed by bromination with N-bromosuccinimide. The X-ray structure showed that this product represents a trans isomer with respect to the amino and hydroxy substituents in the cyclohexyl ring; the dihedral angle between the aminopyrimidine plane and the (noncrystallographic) mirror plane of the substituted cyclohexyl fragment is 33.6 (3)°. Only two of the four potentially ‘active’ H atoms participate in intermolecular N—H⋯O and O—H⋯N hydrogen bonds, linking the molecules into layers parallel to the (10) plane.

(R)-4-[2-(Methyl-sulfanyl)pyrimidin-4-yl]-1-(tetra-hydro-furan-3-yl)-1H-pyrazol-5-amine.

The title compound, C12H15N5OS, was obtained by reaction of 2-(2-(methylthio)pyrimidin-4-yl)-3-oxopropanenitrile with (tetrahydrofuran-3-yl)hydrazine dihydrochloride, and the racemic product was subsequently separated by chiral chromatography (first peak; [α]D 20 = +51.3°). The chiral center at the substituted atom of the tetrahydrofuranyl group has an R-configuration. The pyrimidine and pyrazolyl rings are almost coplanar, their mean planes forming a dihedral angle of 6.4 (1)°. One of the H atoms of the amino group participates in an intramolecular hydrogen bond with the pyrimidine N atom in position 3. The second H atom is involved in an intermolecular hydrogen bond, which links the molecules into an infinite chain.

5-Bromo-3-(indan-1-yl-oxy)pyridin-2-amine.

The title compound, C14H13BrN2O, was obtained by reaction of indan-1-yl methanesulfonate with 2-amino-5-bromopyridin-3-ol in the presence of caesium carbonate. The indane ring system is approximately planar [all but one of the C atoms are coplanar within 0.03 Å, the latter atom being displaced by 0.206 (2) Å from the mean plane through the remaining atoms] and forms a dihedral angle of 58.41 (4)° with the pyridine ring. In the crystal, centrosymmetrically related molecules are linked into dimers by N—H⋯N hydrogen bonds.

5-Chloro-N-[2-(1H-imidazol-4-yl)eth­yl]-N-methyl-7H-pyrrolo[2,3-d]pyrimidin-4-amine

The title compound, C12H13ClN6, was prepared by reaction of 4,5-dichloro-7H-pyrrolo[2,3-d]pyrimidine with 2-(1H-imidazol-4-yl)-N-methylethanamine, and the X-ray study confirmed that chloro-substituent in six-membered ring was replaced in the reaction. The exocyclic N atom environment is approximately coplanar with the pyrrolo[2,3-d]pyrimidine [corresponding dihedral angle is 5.5 (1)°], whereas the mean plane of the N—C—C—C link connecting with the imidazolyl ring is almost exactly orthogonal to the plane of the bicyclic system [dihedral angle = 91.6 (2)°]. The imidazolyl plane itself, however, forms a relatively small dihedral angle of 20.8 (1)° with the pyrrolo[2,3-d]pyrimidine plane. There are two independent N—H⋯N hydrogen bonds in the structure, which link molecules into layers parallel to (03).

2-(6-Bromo-3-pyrid-yl)-8-methyl-imidazo[1,2-a]pyrazine.

The structure of the title compound, C12H9BrN4, prepared by the reaction of 2-bromo-1-(6-bromo-3-pyridyl)ethanone with 2-amino-3-methylpyrazine indicates that the compound with the bromopyridyl substituent at position 2 of the imidazopyrazine fused-ring system represents the major product of this reaction. The plane of the pyridine ring forms a dihedral angle of 16.2 (2)° with the essentially planar (r.m.s. deviation = 0.006 Å) imidazopyrazine system. In the crystal, molecules are linked by weak C—H⋯N interactions.