Methods of Preparation of Aromatic Anils

The aim of this study is to to prepare and identify and characterize the aromatic anils (Schiff.s bases or benzylidene aniline) then used for kinetic study that is cooxidation in presence of oxalic acid by chromic acid in acetic acid medium

Cholest-5-en-3β-yl N-phenyl­carbamate

In the title compound, C34H51NO2, the dihedral angle between the planes of the phenyl ring and the carbonyl group is 9.30 (2)°. No significant inter­molecular inter­actions are observed in the crystal structure. The C5H11 fragment is disordered over two positions with site occupancies of 0.611 (6) and 0.389 (6)

7,7′,8,8′-Tetra­meth­oxy-4,4′-dimethyl-3,3′-bicoumarin

In the crystal structure, the title compound, C24H22O8, lies on a twofold rotation axis and the asymmetric unit comprises one half-mol­ecule. The dihedral angle formed by the coumarin unit with the symmetry-related part is 74.78 (14)°. One of the meth­oxy groups attached to the coumarin unit is considerably twisted, making an angle of 87.17 (17)° with respect to the coumarin unit; the other is twisted by 0.66 (19)°. No classical hydrogen bonds are found in the sturcture; only a weak C—H⋯π inter­action and short intra­molecular O⋯O contacts [2.683 (2)–2.701 (2) Å] are observed

Cyclo­hexane-1,3-diyl bis­(N-phenyl­carbamate)

The asymmetric unit of the title compound, C20H22N2O4, comprises two crystallographically independent mol­ecules (A and B) with slightly different geometries. The dihedral angle between the two terminal phenyl rings is 61.7 (1)° in mol­ecule A and 29.6 (1)° in B. The cyclo­hexane rings adopt chair conformations. In the crystal packing, inter­molecular N—H⋯O hydrogen bonds inter­connect adjacent mol­ecules into a ladder-like structure along the c axis incorporating R 2 2(20) ring motifs. The crystal packing is further stabilized by weak inter­molecular C—H⋯π inter­actions

A novel antimicrobial triterpenic acid from the leaves of Ficus benjamina (var. comosa)

AbstractThe chloroform extract of the leaves of Ficus benjamina (var. comosa) (Moraceae) afforded a new triterpenic acid named as (9,11), (18,19)-disecoolean-12-en-28-oic acid (1) along with β-amyrin (2). Their structures were established on the basis of chemical and physical evidences (IR, 1H NMR, and MS data). The compound 1 exhibited significant antimicrobial activity against Salmonella typhimurium (MTCC-98), Candida albicans (IAO-109), Staphylococcus aureus (IAO-SA-22), Escherichia coli (K-12) and low activity against Aspergillus niger (lab isolate ICAR) and Aspergillus brassicola

9-(3,4-Dimeth­oxy­phen­yl)-3,4,5,6,7,9-hexa­hydroxanthene-1,8(2H)-dione

In the title compound, C21H22O5, the mean planes of the pyran and dimeth­oxy­phenyl rings are nearly perpendicular to one another, with the dihedral angle between them being 88.21 (8)°. The pyran ring adopts a boat conformation whereas the two fused cyclo­hexane rings adopt envelope conformations. In the crystal, mol­ecules are linked into a three-dimensional network by inter­molecular C—H⋯O hydrogen bonds

Redetermination of ethyl (3a-cis)-3a,8b-dihydr­oxy-2-methyl-4-oxo-3a,8b-dihydro-4H-indeno[1,2-b]furan-3-carboxyl­ate monohydrate

The crystal structure of the title compound, C15H14O6·H2O, has been redetermined from single-crystal X-ray data. The structure was originally determined by Peet et al. [J. Heterocycl. Chem. (1995), 32, 33–41] but the atomic coordinates were not reported or deposited in the Cambridge Structural Database. The ethyl substituent is disordered over two sites with refined occupancies of 0.815 (6) and 0.185 (6). The indeno group is almost planar [maximum deviation 0.0922 (14) Å] and makes an angle of 68.81 (4)° with the furan ring. The fused ring molecules are assembled in pairs by intermolecular O—H⋯O hydrogen bonds. The resulting dimers are also hydrogen bonded to the water molecules, forming double-stranded chains running along the a axis

SYNTHESIS, CHARACTERIZATIONAND ANTIMICROBIALACTIVITYOF FRIEDELIN [2, 3-d] SElENADIAZOlE

ABSTRACT The new 1, 2, 3, selenadiazole derivative (3) was prepared from friedelin (1) via the co"esponding semicarbazone (2) using Lalezari cyclization. The compounds were prepared, separated and characterized on the basis of microanalysis and spectral studies. The isolated friedelin and its selenadiazole were screened in vitro for their antimicrobial activities against various pathogenic bacterial were found to be highly active against al/ the selected pathogens. Compound 3 showed an inhibition zone of 14 mm and 12 mm respectively against highly resistant S. albus and C. albicans. A general mechanistic scheme for these reactions is also suggested based on current and previous results

3-(2-Amino-5-nitro­anilino)-5,5-dimethyl­cyclo­hex-2-en-1-one 0.25-hydrate

The asymmetric unit of the title compound, C14H17N3O3·0.25H2O, comprises two independent organic mol­ecules and a water mol­ecule lying on a crystallographic twofold rotation axis with 50% site occupancy. In both independent mol­ecules, the cyclo­hexene rings adopt envelope conformations but superposition of the two molecules shows that the flap atoms point in opposite directions. In the crystal, N—H⋯O and C—H⋯O hydrogen bonds inter­connect adjacent mol­ecules into a three-dimensional network. Weak inter­molecular π–π aromatic stacking inter­actions [centroid–centroid distances = 3.4985 (9) and 3.6630 (9) Å] are also observed

2,3-Dimethyl-6-nitro­quinoxaline

The asymmetric unit of the title quinoxaline compound, C10H9N3O2, contains two crystallographically independent mol­ecules (A and B). The quinoxaline ring systems are essentially planar, with maximum deviations of 0.006 (1) and 0.017 (1) Å, respectively, for mol­ecules A and B. In mol­ecule A, the dihedral angle formed between the quinoxaline ring system and nitro group is 10.94 (3)° [6.31 (13)° for mol­ecule B]. In the crystal, mol­ecules are linked into chains propagating along [001]: one forms zigzag chains linked by C—H⋯O hydrogen bonds, whilst the other forms ladder-like chains by way of C—H⋯N and C—H⋯O hydrogen bonds. The packing is further consolidated by weak π–π inter­actions [range of centroid–centroid distances = 3.5895 (7)–3.6324 (7) Å]