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1.  Crystal structure of (3E)-3-(2,4-di­nitro­phen­oxy­meth­yl)-4-phenyl­but-3-en-2-one 
In the title compound, C17H14N2O6, the conformation about the C=C double bond [1.345 (2) Å] is E, with the ketone moiety almost coplanar [C—C—C—C torsion angle = 9.5 (2)°] along with the phenyl ring [C—C—C—C = 5.9 (2)°]. The aromatic rings are almost perpendicular to each other [dihedral angle = 86.66 (7)°]. The 4-nitro moiety is approximately coplanar with the benzene ring to which it is attached [O—N—C—C = 4.2 (2)°], whereas the one in the ortho position is twisted [O—N—C—C = 138.28 (13)°]. The mol­ecules associate via C—H⋯O inter­actions, involving both O atoms from the 2-nitro group, to form a helical supra­molecular chain along [010]. Nitro–nitro N⋯O inter­actions [2.8461 (19) Å] connect the chains into layers that stack along [001].
doi:10.1107/S1600536814018819
PMCID: PMC4186202  PMID: 25309220
crystal structure; hydrogen bonding; N⋯O inter­actions
2.  Crystal structure of (3E)-3-[(4-nitro­phen­oxy)­meth­yl]-4-phenyl­but-3-en-2-one 
In the title compound, C17H15NO4, the conformation about the C=C double bond [1.348 (2) Å] is E with the ketone group almost co-planar [C—C—C—C torsion angle = 7.2 (2)°] but the phenyl group twisted away [C—C—C—C = 160.93 (17)°]. The terminal aromatic rings are almost perpendicular to each other [dihedral angle = 81.61 (9)°] giving the mol­ecule an overall U-shape. The crystal packing feature benzene-C—H⋯O(ketone) contacts that lead to supra­molecular helical chains along the b axis. These are connected by π–π inter­actions between benzene and phenyl rings [inter-centroid distance = 3.6648 (14) Å], resulting in the formation of a supra­molecular layer in the bc plane.
doi:10.1107/S1600536814018327
PMCID: PMC4186193  PMID: 25309202
crystal structure; hydrogen bonding; π–π inter­actions
3.  Chiral Pharmaceutical Intermediaries Obtained by Reduction of 2-Halo-1-(4-substituted phenyl)-ethanones Mediated by Geotrichum candidum CCT 1205 and Rhodotorula glutinis CCT 2182 
Enzyme Research  2011;2011:976368.
Enantioselective reductions of p-R1-C6H4C(O)CH2R2 (R1 = Cl, Br, CH3, OCH3, NO2 and R2 = Br, Cl) mediated by Geotrichum candidum CCT 1205 and Rhodotorula glutinis CCT 2182 afforded the corresponding halohydrins with complementary R and S configurations, respectively, in excellent yield and enantiomeric excesses. The obtained (R)- or (S)-halohydrins are important building blocks in chemical and pharmaceutical industries.
doi:10.4061/2011/976368
PMCID: PMC3113109  PMID: 21687613
4.  Ethyl (2Z)-3-oxo-2-(3,4,5-tri­meth­oxy­benzyl­idene)butano­ate 
In the title compound, C16H20O6, the conformation about the C=C double bond [1.344 (2) Å] is Z. With respect to this bond, the ketone is almost coplanar [C—C—C—O torsion angle = −179.60 (10)°] and the ester is almost perpendicular [C—C—C—O = 78.42 (13)°]. The meth­oxy substituents of the central benzene ring are either almost coplanar [C—C—O—C = 3.54 (15) and 177.70 (9)°] or perpendicular [C—C—O—C = 80.08 12)° for the central substituent]. In the crystal, the three-dimensional architecture features C—H⋯O and π–π [inter-centroid distance = 3.6283 (6) Å] inter­actions.
doi:10.1107/S1600536813023374
PMCID: PMC3884456  PMID: 24427096
5.  Effect of immobilized cells in calcium alginate beads in alcoholic fermentation 
AMB Express  2013;3:31.
Saccharomyces cerevisiae cells were immobilized in calcium alginate and chitosan-covered calcium alginate beads and studied in the fermentation of glucose and sucrose for ethanol production. The batch fermentations were carried out in an orbital shaker and assessed by monitoring the concentration of substrate and product with HPLC. Cell immobilization in calcium alginate beads and chitosan-covered calcium alginate beads allowed reuse of the beads in eight sequential fermentation cycles of 10 h each. The final concentration of ethanol using free cells was 40 g L-1 and the yields using glucose and sucrose as carbon sources were 78% and 74.3%, respectively. For immobilized cells in calcium alginate beads, the final ethanol concentration from glucose was 32.9 ± 1.7 g L-1 with a 64.5 ± 3.4% yield, while the final ethanol concentration from sucrose was 33.5 ± 4.6 g L-1 with a 64.5 ± 8.6% yield. For immobilized cells in chitosan-covered calcium alginate beads, the ethanol concentration from glucose was 30.7 ± 1.4 g L-1 with a 61.1 ± 2.8% yield, while the final ethanol concentration from sucrose was 31.8 ± 6.9 g L-1 with a 62.1 ± 12.8% yield. The immobilized cells allowed eight 10 h sequential reuse cycles to be carried out with stable final ethanol concentrations. In addition, there was no need to use antibiotics and no contamination was observed. After the eighth cycle, there was a significant rupture of the beads making them inappropriate for reuse.
doi:10.1186/2191-0855-3-31
PMCID: PMC3695878  PMID: 23721664
Immobilized cells; Fermentation; Ethanol; Glucose; Sucrose; Alginate
6.  Ethyl (2E)-2-(2H-1,3-benzodioxol-5-yl­methyl­idene)-4-chloro-3-oxobutano­ate 
In the title compound, C14H13ClO5, the five-membered ring is in an envelope conformation with the methyl­ene C-atom being the flap. The conformation about the C=C double bond [1.341 (2) Å] is E. The chloro­propan-2-one residue is approximately orthogonal to the remaining mol­ecule [dihedral angle = 88.03 (6)°]. In the crystal, the mol­ecules associate via C—H⋯O inter­actions, involving both carbonyl-O atoms, giving rise to an undulating two-dimensional array in the ac plane.
doi:10.1107/S1600536811011780
PMCID: PMC3089165  PMID: 21754371
7.  Ethyl (E)-2-methoxy­imino-2-(4-nitro­benzo­yl)acetate 
The title mol­ecule, C12H12N2O6, features an E conformation about the oxime group. The methoxy­imino and ester residues are effectively coplanar with each other (r.m.s. deviation for the nine non-H atoms = 0.127 Å) and almost orthogonal [with dihedral angles of 99.44 (13) and −77.85 (13)°, respectively] to the carbonyl and nitro­phenyl groups which lie to either side of this central plane. The crystal structure is consolidated by C—H⋯O contacts.
doi:10.1107/S1600536810001583
PMCID: PMC2979917  PMID: 21579817
8.  (Z)-Ethyl 2-hydroxy­imino-2-(4-nitro­benz­yl)ethanoate 
The title mol­ecule, C11H10N2O6, has a Z conformation about the C=N bond of the oxime unit. There are significant twists from planarity throughout the mol­ecule, the most significant being between the hydroxy­imino and ester groups which are effectively orthogonal with an N—C—C—Ocarbon­yl torsion angle of 91.4 (2)°. The crystal packing features oxime–benzoyl O—H⋯O contacts that lead to chains along [010] and C—H⋯O interactions also occur.
doi:10.1107/S1600536809052386
PMCID: PMC2980268  PMID: 21580028

Results 1-8 (8)