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Total lipid contents of green (Chlorella pyrenoidosa, C), red (Porphyra tenera, N; Palmaria palmata, D), and brown (Laminaria japonica, K; Eisenia bicyclis, A; Undaria pinnatifida, W, WI; Hizikia fusiformis, H) commercial edible algal and cyanobacterial (Spirulina platensis, S) products, and autotrophically cultivated samples of the green microalga Chlorella kessleri (CK) and the cyanobacterium Spirulina platensis (SP) were determined using a solvent mixture of methanol/chloroform/water (1:2:1, v/v/v, solvent I) and n-hexane (solvent II). Total lipid contents ranged from 0.64% (II) to 18.02% (I) by dry weight and the highest total lipid content was observed in the autotrophically cultivated cyanobacterium Spirulina platensis. Solvent mixture I was found to be more effective than solvent II. Fatty acids were determined by gas chromatography of their methyl esters (% of total FAMEs). Generally, the predominant fatty acids (all results for extractions with solvent mixture I) were saturated palmitic acid (C16:0; 24.64%–65.49%), monounsaturated oleic acid (C18:1(n-9); 2.79%–26.45%), polyunsaturated linoleic acid (C18:2(n-6); 0.71%–36.38%), α-linolenic acid (C18:3(n-3); 0.00%–21.29%), γ-linolenic acid (C18:3(n-6); 1.94%–17.36%), and arachidonic acid (C20:4(n-6); 0.00%–15.37%). The highest content of ω-3 fatty acids (21.29%) was determined in Chlorella pyrenoidosa using solvent I, while conversely, the highest content of ω-6 fatty acids (41.42%) was observed in Chlorella kessleri using the same solvent.

The alkaline milieu of chronic wounds severely impairs the therapeutic effect of antibiotics, such as rifampicin; as such, the development of new drugs, or the smart delivery of existing drugs, is required. Herein, two innovative polyelectrolyte nanoparticles (PENs), composed of an amphiphilic chitosan core and a polycationic shell, were synthesized at alkaline pH, and in vitro performances were assessed by 1H NMR, elemental analysis, FT-IR, XRD, DSC, DLS, SEM, TEM, UV/Vis spectrophotometry, and HPLC. According to the results, the nanostructures exhibited different morphologies but similar physicochemical properties and release profiles. It was also hypothesized that the simultaneous use of the nanosystem and an antioxidant could be therapeutically beneficial. Therefore, the simultaneous effects of ascorbic acid and PENs were evaluated on the release profile and degradation of rifampicin, in which the results confirmed their synergistic protective effect at pH 8.5, as opposed to pH 7.4. Overall, this study highlighted the benefits of nanoparticulate development in the presence of antioxidants, at alkaline pH, as an efficient approach for decreasing rifampicin degradation.

A new hyaluronan derivative modified with β-cyclodextrin units (CD-HA) was prepared via the click reaction between propargylated hyaluronan and monoazido-cyclodextrin (CD) to achieve a degree of substitution of 4%. The modified hyaluronan was characterized by 1H-nuclear magnetic resonance spectroscopy (NMR) and size exclusion chromatography. Subsequent 1H-NMR and isothermal calorimetric titration experiments revealed that the CD units on CD-HA can form virtual 1:1, 1:2, and 1:3 complexes with one-, two-, and three-site adamantane-based guests, respectively. These results imply that the CD-HA chains used the multitopic guests to form a supramolecular cross-linked network. The free CD-HA polymer was readily restored by the addition of a competing macrocycle, which entrapped the cross-linking guests. Thus, we demonstrated that the new CD-HA polymer is a promising component for the construction of chemical stimuli-responsive supramolecular architectures.

The asymmetric unit of the title compound, C15H17N5, consists of two molecules in which the dihedral angles between the best planes of the purine ring system (r.m.s. deviations = 0.0060 and 0.0190 Å) and the benzene ring are 89.21 (3) and 82.14 (4)°. The molecules within the asymmetric unit are linked into dimers by pairs of N—H...N hydrogen bonds. Weak C—H...π contacts and π–π interactions [centroid–centroid = 3.3071 (1) Å] further connect the molecules into a three-dimensional network.

In the molecule of the title compound, C25H24FN, the dihedral angle between the best planes of the quinoline fragment (rings A and B) and the benzene ring (C) is 9.51 (4)°. In the crystal, molecules are linked into centrosymmetric dimers via pairs of weak C—H...F interactions. The molecules are stacked into chains along the a axis by weak off-set π–π interactions between the A and C rings of translation-related molecules with a centroid–centroid distance of 3.6440 (2) Å.

The conformation of the title compound, C27H34O, is stabilized by a weak intramolecular C—H...π interaction. The dihedral angle between the benzene rings is 54.79 (4)°. The adamantane cage consists of three fused cyclohexane rings in classical chair conformations, with C—C—C angles in the range 107.75 (10)–111.35 (9)°. Although the molecule contains a hydroxy group as a conceivable hydrogen-bond donor, this group is sterically hindered by bulky substituents and no hydrogen bonds are observed in the crystal structure.

In the title compound, C10H14ClN5, the purine ring system is essentially planar, with an r.m.s. deviation from the least-squares plane defined by the nine constituent atoms of 0.0063 (11) Å. In the crystal, molecules are linked by weak N—H...N and C—H...π interactions.

The title compound, C11H13NO2S2, contains a 1,3-dithiane ring in an almost ideal chair conformation with the following puckering parameters: Q = 0.7252 (15) Å, θ = 6.71 (13) and ϕ = 50.4 (11)°. The benzene ring occupies an axial position at the dithiane ring. The nitro group is almost coplanar with the benzene ring [O—N—C—C = −3.2 (2)°]. The molecule has an L-shape with a C—C—C—C torsion angle of −74.15 (17)° for the atoms of the methyl group and the dithiane–benzene linkage. The crystal packing is stabilized only via weak non-specific van der Waals interactions.

In the title molecule, C8H8Cl2N4, the essentially planar imidazole and pyrimidine rings [maximum deviations of 0.0030 (15) and 0.0111 (15) Å, respectively] make a dihedral angle of 1.32 (8)°. In the crystal, the fused-ring systems are stacked approximately parallel to the bc plane, with a centroid–centroid distance between inversion-related pyrimidine rings of 3.5189 (9) Å.

In the crystal sructure of the title compound, C17H21NO, the molecular packing is stabilized by intermolecular N—H...O hydrogen bonds and additional weak N—H...π interactions, forming chains that propagate along the b axis. Conjugation of the carbonyl group and the benzene ring is rather attenuated due to a twisting of the carbonyl group from the plane of the benzene ring [torsion angle = 27.1 (2)°].

The asymmetric unit of the title compound, C18H22N2, contains two independent molecules which differ slightly with respect to the torsion angles involving the atoms joining the adamantyl and benzimidazole groups. The bond angles in the adamantane cage vary within the range 108.27 (9)–110.55 (10)°. The benzimidazole ring system in both molecules is essentially planar, the maximum deviations from the best planes being 0.0134 (15) and 0.0229 (14) Å. In the crystal, weak C—H...π interactions link the molecules.

In the crystal structure of the title compound, C18H25NO, molecules are linked via O—H...N hydrogen bonds, forming chains parallel to the c axis. Additional weak N—H...O interactions stabilize the crystal packing. The adamantane cage consists of three fused cyclohexane rings in almost ideal chair conformations, with C—C—C angles in the range 107.9 (10)–111.3 (11)°.

The title compound, C11H17Br, has crystallographically imposed mirror symmetry in the solid state with molecules bisected by mirror planes parallel to the crystallographic ac plane (five C atoms, three H atoms and the Br atom lie on the mirror plane). The asymmetric unit contains one half-molecule. The crystal packing is stabilized only via weak non-specific van der Waals interactions.

In the title compound, C18H22O, the dihedral angle between the carbonyl and benzene planes is 69.11 (6)°. In the adamantyl group, the three fused cyclohexane rings have almost ideal chair conformations, with C—C—C angles in the range 108.14 (11)–110.50 (11)°. No specific intermolecular interactions (other than van der Waals interactions) are present in the crystal.

In the crystal of the title compound, C14H17NO2, molecules are arranged into chains along the b axis linked via O—H...O hydrogen bonds. While the benzene ring is essentially planar, with a maximum deviation from the best plane of 0.003 (1) Å, the pyridine ring is slightly V-shaped: the distance of the carbonyl C atom from the benzene best plane is 0.120 (1) Å. The hydroxy group is inclined markedly towards the benzene ring reducing the C—C—O bond angle to 113.21 (10)°.

The asymmetric unit of the title compound, C18H23NO2, consists of two crystallographically independent molecules bearing an adamantane cage consisting of three fused cyclohexane rings in almost ideal chair conformations, with C—C—C angles in the range 108.47 (16)–110.59 (15)°. Both aryl rings are essentially planar, the maximum deviation from the best plane being 0.0125 (19) Å. One conformer forms chains parallel to the b axis via N—H...O hydrogen bonds, whereas the second exhibits only an intramolecular N—H...O hydrogen bond. The crystal structure is stabilized by further weak N—H...O and N—H...N interactions.

In the title compound, C25H30O, the adamantane cage consists of three fused cyclohexane rings in classical chair conformations, with C—C—C angles in the range 107.15 (9)–111.55 (9)°. The dihedral angle between the benzene rings is 46.91 (4)° and the conformation is stabilized by a weak intramolecular C—H...π interaction.

In the title compound, C18H24, the adamantane cage consists of three fused cyclohexane rings in almost ideal chair conformations, with C—C—C angles in the range 108.0 (14)–111.1 (15)°. The phenyl and 1-adamantyl substituents adopt anti orientations with a C—C—C—C torsion angle of 177.10 (16)°. In the crystal packing, the molecules are linked by weak C—H...π interactions into chains along the a axis.

In the title compound, C23H26O, the adamantane cage consists of three fused cyclohexane rings in classical chair conformations with absolute values of the C—C—C angles in the range 106.57 (11)–111.56 (12)°. The dihedral angle between the two phenyl rings is 81.38 (4)°. Although a hydroxy group is present as a conceivable donor, no hydrogen bonds are observed in the crystal structure.

The structure of the title compound, C26H31NO12, contains an essentially planar quinoline skeleton, with the maximum deviation from the best plane being 0.055 (2) Å, and an oxane ring in a classical chair conformation with the following Cremer and Pople puckering parameters: Q = 0.586 (2) Å, θ = 11.5 (2)° and ϕ = 309.4 (10)°. One acetyl group displays rotational disorder with occupancies of 0.634 (8):0.366 (8). The crystal packing is stabilized by N—H...O hydrogen bonds, which link molecules into chains along the a axis. The packing is further stabilized by weak C—H...O interactions. The absolute configurations on the carbons in the oxane ring correspond to those of the commercial starting material and are unchanged in the well known mechanism of the Koenigs–Knorr synthesis.

The asymmetric unit of the title compound, C9H5Cl2N, consists of two crystallographically independent molecules. In both molecules the quinoline ring system is essentially planar [maximum deviations from the best plane of 0.0232 (13) 0.0089 (15) Å]. The angle between these planes is 22.40 (3)°. Conformers A and B are arranged face-to-face along the c axis, forming alternating pairs in the order AABB. The interplanar distances AA, AB and BB are 3.3166 (11), 3.2771 (11) and 3.3935 (11) Å, respectively. The crystal packing is stabilized by weak C—H...Cl and C—H...N interactions.

In the title compound, C10H14ClN5, the imidazole and pyrimidine rings are essentially planar [maximum deviation = 0.0013 (14) and 0.0207 (13) Å, respectively]. In the crystal, the molecules are linked by weak C—H...N interactions into chains parallel to the c axis and the crystal packing is stabilized by additional weak C—H...N and C—H...Cl interactions.

The structure of the title compound, C26H28N2O2, contains essentially planar quinoline and benzene rings, the maximum deviations from the best plane being 0.086 (2) and 0.0056 (19) Å, respectively; the dihedral angle between the rings is 82.87 (4)°. The adamantane cage consists of three fused cyclohexane rings in classical chair conformations, with C—C—C angles in the range 107.85 (15)–111.35 (15)°. Enantiomers are linked alternately into chains along the c axis via short N—H...O interactions and further C–H...π interactions stabilize pairs of enantiomers, forming a two-dimensional network.

The asymmetric unit of the title compound, C25H30ClN5, consists of two molecules with slightly different geometrical parameters. The dihedral angles between the purine and benzene rings are 39.54 (5) and 23.69 (5)° in the two molecules. The adamantane cages consist of three fused cyclohexane rings in classical chair conformations, with C—C—C angles in the range 108 (2)–111 (2)°. In the crystal, molecules are linked into dimers via two N—H...N hydrogen bonds.

In the title compound, C28H32O2, the oxanone ring adopts distorted half-boat conformation with the following Cremer and Pople puckering parameters: Q = 0.619 (2) Å, θ = 0.75 (19) and ϕ = 172 (13)°. The dihedral angle betwen two benzene rings is 21.32 (7)°. The adamantane unit consists of three fused cyclohexane rings in classical chair conformations, with absolute values of C—C—C—C torsion angles in the range 57.5 (2)–60.9 (2)°. Weak interactions of the type C—H...O link molecules of each enantiomer into chains parallel to the b axis and lying about inversion centers. The crystal packing is also stabilized by intermolecular π-π stacking interactions [centroid–centroid distance of 3.8566 (11) Å].

In the title compound, C26H30ClN5O·CHCl3, the purine molecule consists of essentially planar benzene and purine ring systems [maximum deviation 0.010 (4) Å for both ring systems] forming a dihedral angle of 85.52 (9)°. Intermolecular N—H...N hydrogen bonds link adjacent molecules into centrosymmetric dimers. The structure also contains intermolecular C—H...O and C—H...N interactions. The benzene rings form offset face-to-face π–π stacking interactions with an interplanar distance of 3.541 (4) Å and a centroid-to-centroid distance of 4.022 (4) Å.

In the title salt, C12H20NO+·CH3SO3−, the [1-(1-adamantylamino)ethylidene]oxonium cations and methanesulfonate anions are linked into chains along the a axis via O—H...O and N—H...O hydrogen bonds. All non-H atoms of the acetamido group are essentially planar, with a maximum deviation of 0.0085 (12) Å. In comparison with related structures, the carbonyl C=O bond is slightly elongated [1.249 (2) Å], whereas the amide C—N bond is shortened [1.292 (2) Å].

In the racemic crystal of the title compound, C17H23NO, enantiomers of the two crystallographically independent molecules are linked into face-to-face RSdimers via intermolecular O—H...N hydrogen bonds and π–π interactions with centroid–centroid distances of 3.7610 (2) Å. The molecules adopt slightly different conformations and contain an adamantane cage consisting of three fused cyclohexane rings in almost ideal chair conformations, with C—C—C angles varying within the range 107.2 (4)–111.4 (4)°. In the hydrogen-bonded pair, the benzene rings are almost coplanar, the dihedral angle between them being 1.29 (13)°. The molecular packing in the crystal is stabilized by additional intermolecular N—H...O hydrogen bonds.

The structure of the title compound, C27H32ClN5O, consists of two crystallographically independent conformers differing slightly in all geometric parameters. Both contain nearly planar purine and benzene ring systems [maximum deviations of 0.046 (3) and 0.005 (2) Å, respectively], the dihedral angles between them being 76.44 (6) and 82.39 (6)°, and an adamantane cage consisting of three fused cyclohexane rings in almost ideal chair conformations, with C—C—C angles in the range 108.7 (2)–110.6 (2)°. The carbonyl plane and the benzene ring are almost coplanar [dihedral angles of 6.43 (9) and 0.64 (8)° in the two conformers]. The crystal structure is stabilized by intermolecular N—H...N interactions that link adjacent molecules into dimers and by some non-bonding contacts of the C—H...Cl type.