4-Azido-2-chloro-6-methyl-quinoline

In the title compound, C(10)H(7)ClN(4), the quinoline ring system is planar [maximum deviation 0.0035 (10) Å]. The crystal structure is stabilized by van der Waals and π-π stacking inter-actions [centroid-centroid distance 3.6456 (17) Å].

Glycinium hydrogen fumarate glycine solvate monohydrate

In the title compound, C₂H₆NO₂⁺·C₄H₃O₄⁻·C₂H₅NO₂·H₂O, the asymmetric unit contains two glycine residues, one protonated and one in the zwitterionic form, a hydrogen fumarate anion and a water mol­ecule. Through N—H⋯O and O—H⋯O hydrogen bonds, mol­ecules assemble in layers parallel to the (10) plane, one layer of hydrogen fumarate anions alternating with two layers of glycine mol­ecules. In each glycine layer, hydrogen bonds generate an R₄⁴(19) graph-set motif. Further hydrogen bonds involving the water mol­ecule and the hydrogen fumarate anions result in the formation of a three-dimensional network.

2,4,6,8-Tetra-kis(4-fluoro-phen-yl)-3,7-diaza-bicyclo-[3.3.1]nonan-9-one

In the title compound, C(31)H(24)F(4)N(2)O, the bicyclo-[3.3.1]nonane ring exists in a chair-boat conformation. Two of the four fluorine-substituted rings adopt equatorial dispositions with the piperidin-4-one rings. Mol-ecules are linked into a two-dimensional network parallel to (01) by N-H⋯O, C-H⋯F and C-H⋯O hydrogen bonds. Inter-molecular N-H⋯π and C-H⋯π inter-actions are also observed.

Hexaaquazinc(II) dipicrate

In the title compound, [Zn(H₂O)₆](C₆H₂N₃O₇)₂, the Zn^II ion is located on an inversion center and is coordinated by six water mol­ecules in an octa­hedral geometry. The picrate anions have no coordination inter­actions with the Zn^II atom. The three nitro groups are twisted away from the attached benzene ring by19.8 (3), 6.5 (4) and 28.6 (3)°. There are numerous O—H⋯O hydrogen bonds in the crystal structure.

Pityriasis lichenoides: the differences between children and adults

BACKGROUND

Pityriasis lichenoides (PL) is a skin disease that affects both children and adults. Anecdotally, it is said to run a more benign course in children, with a frequent tendency to self-resolution. However, to our knowledge, there have been no published studies comparing PL in both age groups.

OBJECTIVE

To evaluate the clinicopathological features, overall efficacy of treatments and disease outcomes in children and adults diagnosed with PL.

METHODS

A retrospective review of records was undertaken on all patients diagnosed with PL at two regional centres during an 8-year period (from 1998 to 2006). For each individual, data were collected on age, sex, number of lesions, lesional morphology and distribution, symptoms, histopathological features, treatment modalities (and response), overall follow-up and length of remission.

RESULTS

We recorded 25 children (median age 8 years, range 2-18) and 32 adults (median age 40 years, range 20-65) with PL. All the children and adults had more than 20 scaly, papular lesions. Children had greater lesional body involvement than adults. Lesions on the legs and trunk were present in 23 children (92%) compared with 19 adults (59%) (P < 0.01) and facial involvement was observed more commonly in children (n = 10, 40%) compared with adults (n = 8, 25%). Dyspigmentation was significantly more common in children (n = 18, 72%) compared with adults (n = 6, 19%) (P < 0.001). Topical corticosteroids were used by 16 children (64%) and 18 adults (56%) but only half in each group found these effective. Eight children (32%) were treated with erythromycin, with only two (25%) clearing, and one of these subsequently relapsing. In contrast, four adults (13%) received antibiotics, with three (75%) clearing and none relapsing thereafter. Ultraviolet B phototherapy was used in eight children (32%), with seven (88%) completely or almost clearing, but four (57%) subsequently relapsed. Fourteen adults (44%) received phototherapy; 10 (71%) completely cleared and only two of these (20%) subsequently relapsed. Strikingly, after a median disease duration of 30 months, only five children (20%) went into complete remission compared with 25 adults (78%) (P < 0.001).

CONCLUSIONS

This is the first study to compare PL in children and adults. Our findings suggest that, compared with adults, PL in children is more likely to run an unremitting course, with greater lesional distribution, more dyspigmentation and a poorer response to conventional treatment modalities.

Combined aniridic intraocular lens implantation and vitreoretinal surgery

A 45-year-old man presented with post-traumatic aniridia. We describe the combined surgery done to treat both aniridia and epiretinal membrane simultaneously. A combined aniridia intraocular lens and vitreoretinal surgery was done. The case report highlights the advantage of combined surgery in terms of cost factor and surgical time.

1'-Methylcyclooctane-1-spiro-3'-pyrrolidine-2'-spiro-3''-indoline-2,2''-dione and 1,1'-dimethylpiperidine-3-spiro-3'-pyrrolidine-2'-spiro-3''-indoline-2'',4-dione

In both title compounds, C(19)H(24)N(2)O(2), (I), and C(17)H(21)N(3)O(2), (II), respectively, there are two molecules in the asymmetric unit and the pyrrolidine rings adopt envelope conformations. The conformations of the cyclooctane [in (I)] and 1-methylpiperidone [in (II)] rings are boat-chair and chair, respectively. The indolin-2-one group is almost perpendicular to the pyrrolidine ring. Intermolecular C-H...O, N-H...O and N-H...N interactions provide stability to the structures.

4-Carboxyanilinium (2R,3R)-tartrate and a redetermination of the α-polymorph of 4-aminobenzoic acid

In the title compounds, 4-carboxyanilinium (2R,3R)-tartrate, C(7)H(8)NO(2)+.C(4)H(5)O(6)-, (I), and 4-aminobenzoic acid, C(7)H(7)NO(2), (II), the carboxyl planes of the 4-carboxyanilinium cations/4-aminobenzoic acid are twisted from the aromatic plane. In (I), the characteristic head-to-tail interactions are observed through the tartrate anions, forming two C2(2)(7) chain motifs propagating parallel to the a and c axes of the unit cell. Also, the tartrate anions are connected through two primary C1(1)(6) and C1(1)(7) chain motifs, leading to a secondary R4(4)(22) ring motif. In (II), head-to-tail interaction is seen through a discrete D1(1)(2) motif and carboxyl group dimerization is observed through centrosymmetrically related R2(2)(8) motifs around the inversion centres of the unit cell. The crystal structures of both compounds are stabilized by intricate three-dimensional hydrogen-bonding networks. Alternate hydrophobic and hydrophilic layers are observed in (I) as a result of a column-like arrangement of the anions and the aromatic rings of the cations.

(R)-3,5-Bis[(E)-benzylidene]-1-(1-phenylethyl)piperidin-4-one, 3,5-bis[(E)-4-chlorobenzylidene]-1-[(R)-1-phenylethyl]piperidin-4-one and 3,5-bis[(E)-2-chlorobenzylidene]-1-[(R)-1-phenylethyl]piperidin-4-one

Polysubstituted piperidones, viz. the title compounds, C(27)H(25)NO, (I), C(27)H(23)Cl(2)NO, (II), and C(27)H(23)Cl(2)NO, (III), adopt sofa conformations. The molecular packing in (I) and (II) is a result of van der Waals interactions, whereas in (III), a C-H...O interaction is also found.