A Multi-Analytical Approach for the Evaluation of the Efficiency of the Conservation-Restoration Treatment of Moroccan Historical Manuscripts Dating to the 16th, 17th, and 18th Centuries.

The most critical steps during the conservation-restoration treatment applied in Moroccan libraries are the deacidification using immersion in a saturated aqueous calcium hydroxide (Ca(OH)2) solution and the consolidation of degraded manuscripts using Japanese paper. The present study aims to assess the efficiency of this restoration method using a multi-analytical approach. For this purpose, three ancient Arabic Moroccan manuscript papers dating back to the 16th, 17th, and 18th centuries were investigated to characterize the paper support and make a comparative study between pre-restoration and post-restoration states. Three structural and molecular characterization techniques including solid-state nuclear magnetic resonance spectroscopy on (13)C with cross-polarization and magic-angle spinning nuclear magnetic resonance ((13)C CP-MAS NMR), attenuated total reflectance Fourier transform infrared spectroscopy (ATR FT-IR), and X-ray diffraction (XRD) were used to elucidate the cellulose main features, to identify the inorganic composition of the papers, and to study the crystallinity of the samples. Inductively coupled plasma atomic emission spectrometry (ICP-AES) allowed us to obtain a qualitative and quantitative characterization of the mineral fillers used in the manufacturing of the papers. Scanning electron microscopy coupled to energy dispersive spectrometry (SEM-EDS) ascertained the state of conservation of the different papers and helped us to study the elemental composition of the samples. After restoration, it was shown that the deacidification improved the stability of papers by providing an important alkaline buffer, as demonstrated using FT-IR and energy dispersive spectrometry (EDS) results. However, XRD and ICP-AES did not confirm the pertinence of the treatment for all samples because of the unequal distribution of Ca on the paper surface during the restoration. The consolidation process was studied using SEM analysis; its effectiveness in restoring torn areas was found to be significant.

Crystal structure of ethyl 2-amino-4-(4-meth-oxy-phen-yl)-4H-1-benzothieno[3,2-b]pyran-3-carboxyl-ate.

The mol-ecule of the title compound, C21H19NO4S, features a fused ring system whereby a five-membered ring is flanked by two six-membered rings. This is linked to an ethyl 3-carboxyl-ate group and to a meth-oxy-benzene group. The fused-ring system is quasi-planar, with the greatest deviation from the mean plane being 0.131 (1) Šfor the methine C atom. The plane through the meth-oxy-benzene ring is nearly perpendicular to that through the fused-ring system, as indicated by the dihedral angle of 85.72 (6)°. An intra-molecular N-H⋯O hydrogen bond is noted. In the crystal, mol-ecules are linked by N-H⋯O hydrogen bonds, forming layers that stack along the a axis.

Crystal structure of 2-amino-3-cyano-4-(4-meth-oxy-phen-yl)-4H-1-benzo-thieno[3,2-b]pyran.

The three fused five- and six-membered rings in the title compound, C19H14N2O2S, are virtually coplanar, with the maximum deviation from the mean plane being 0.060 (1) Å. This benzothieno[3,2-b]pyran ring system is nearly perpendic-ular to the plane of the 4-meth-oxy-phenyl ring, forming a dihedral angle of 83.65 (5)°. In the crystal, mol-ecules are linked by pairs of N-H⋯N hydrogen bonds into inversion dimers. The dimeric units are further connected by an N-H⋯O hydrogen bond into a tape running along the b axis. The tapes are linked together by C-H⋯N and π-π inter-actions [centroid-centroid distance = 3.7743 (8) Å], forming a three-dimensional network.

Conservation of Moroccan manuscript papers aged 150, 200 and 800 years. Analysis by infrared spectroscopy (ATR-FTIR), X-ray diffraction (XRD), and scanning electron microscopy energy dispersive spectrometry (SEM-EDS).

The preservation of manuscripts and archive materials is a serious problem for librarians and restorers. Paper manuscript is subjected to numerous degradation factors affecting their conservation state. This research represents an attempt to evaluate the conservation restoration process applied in Moroccan libraries, especially the alkaline treatment for strengthening weakened paper. In this study, we focused on six samples of degraded and restored paper taken from three different Moroccan manuscripts aged 150, 200 and 800 years. In addition, the Japanese paper used in restoration has been characterized. A modern paper was also analyzed as reference. A three-step analytical methodology based on infrared spectroscopy (ATR-FTIR), X-ray diffraction (XRD) and scanning electron microscopy coupled to energy dispersive spectrometry (SEM-EDS) analysis was developed before and after restoration in order to determine the effect of the consolidation treatment on the paper structure. The results obtained by XRD and ATR-FTIR disclosed the presence of barium sulfate (BaSO4) in all restored paper manuscripts. The presence of calcium carbonate (CaCO3) in all considered samples was confirmed by FTIR spectroscopy. The application of de-acidification treatment causes significant changes connected with the increase of intensity mostly in the region 1426 cm(-1), assigned to the asymmetric and symmetric CO stretching mode of calcite, indicating the effectiveness of de-acidification procedure proved by the rise of the alkaline reserve content allowing the long term preservation of paper. Observations performed by SEM magnify the typical paper morphology and the structure of fibbers, highlighting the effect of the restoration process, manifested by the reduction of impurities.

Ethyl 2-amino-4-phenyl-4H-1-benzo-thieno[3,2-b]pyran-3-carboxyl-ate.

The title heterocyclic compound, C(20)H(17)NO(3)S, was synthesized by condensation of ethyl cyano-acetate with (Z)-2-benzyl-idenebenzo[b]thio-phen-3(2H)-one in the presence of a basic catalyst in ethanol. The phenyl and ester groups make dihedral angles of 77.67 (6) and 8.52 (6)°, respectively, with the benzothienopyran ring system [maximum r.m.s. deviation = 0.1177 (13) Å]. In the crystal, centrosymmetric dimers are formed through pairs of N-H⋯O hydrogen bonds between the amine and ester groups. Inter-molecular C-H⋯N hydrogen bonds and C-H⋯π inter-actions involving the thio-phene ring are also observed.

(2RS,4'RS)-3'-(3-Chloro-4-meth-oxy-phen-yl)-4'-phenyl-4'H-spiro-[indene-2,5'-isoxazol]-1(3H)-one ethanol monosolvate.

The title compound, C(23)H(17)ClN(2)O(3)·C(2)H(6)O, is the stoichiometric 1:1 ethanol solvate of a racemic reaction product, which forms a conglomerate. The refined Flack parameter of 0.36 (3) indicates racemic twinning. In the structure, mol-ecules are linked into zigzag chains by a series of inter-molecular N-H⋯O and O-H⋯O hydrogen bonds.

(2E)-2-Benzyl-idene-4-ethyl-3,4-dihydro-naphthalen-1(2H)-one.

In the title compound, C(19)H(18)O, the exocyclic C=C double bond has an E configuration. The ethyl substituent on the cyclo-hexa-none ring is in an axial position. The cyclo-hexa-none ring adopts a half-chair conformation, presumably due to conjugation in the benzene ring.

(2E)-4-tert-Butyl-2-(4-meth-oxy-benzyl-idene)-3,4-dihydro-naphthalen-1(2H)-one.

In the title compound C(22)H(24)O(2), the exocyclic C=C double bond is in an E configuration and the tert-butyl group is in an axial position on the cyclo-hexa-none ring. The cyclo-hexa-none ring in the dihydro-naphthalene fused-ring system adopts a half-chair conformation in both independent two mol-ecules in the asymetric unit. The benzene ring system is oriented angles of 43.97 (12) and 39.24 (12)° with respect to the naphthyl ring system in the two independent mol-ecules. In the crystal, mol-ecules are linked via C-H⋯O hydrogen bonds and C-H⋯π inter-actions.

3'-(4-Meth-oxy-phen-yl)-4'-phenyl-3H,4'H-spiro-[1-benzothio-phene-2,5'-isoxazol]-3-one.

In the title compound, C(23)H(17)NO(3)S, the thio-phene and isoxazole rings each have an envelope conformation with the spiro C atom linking them forming the flap of the envelope in each case. The dihedral angle between the mean planes of the benzothio-phene ring and isoxazole rings is 81.35 (7)°. In the crystal, an inter-molecular C-H⋯O hydrogen bond links the mol-ecules into a chain running parallel to the a axis.

4-tert-Butyl-3',4'-bis-(4-methyl-phen-yl)-3,4-dihydro-1H,4'H-spiro-[naphthalene-2,5'-[1,2]oxazol]-1-one.

In the title compound, C(30)H(31)NO(2), the cyclo-hexa-none ring in the naphthalene fused-ring system adopts a half-chair conformation, presumably due to conjugation of the benzene ring. The naphthalene ring system makes dihedral angles of 86.63 (7), 65.15 (8) and 63.18 (8)° with respect to the two methyl-benzene planes and the 1,2-oxazole ring system. Inter-molecular C-H⋯O and C-H⋯N hydrogen bonding and C-H⋯π inter-actions stabilize the crystal structure. The H atoms of the two methyl groups of the methyl-phenyl groups are disordered over two positions with equal occupancies.

Simple and efficient synthesis of racemic 2-(tert-butoxycarbon-ylamino)-2-methyl-3-(1H-1,2,4-triazol-1-yl)propanoic acid, a new derivative of ß-(1,2,4-triazol-1-yl)alanine.

A simple synthetic approach to racemic N-tert-butyloxycarbonyl-2-methyl-3-(1H-1,2,4-triazol-1-yl)alanine (5) in four steps and 68% overall yield starting from oxazoline derivative 1 is reported. This synthesis involves the alkylation of 1H-1,2,4-triazole with an O-tosyloxazoline derivative, followed by an oxazoline ring-opening reaction and oxidation of the N-protected ß­aminoalcohol by potassium permanganate.

Diethyl 2-{(dibenzyl-amino)[4-(trifluoro-meth-yl)phen-yl]meth-yl}malonate.

The asymmetric unit of the title compound, C(29)H(30)F(3)NO(4), contains two independent mol-ecules. In each independent mol-ecule, one of two terminal ethyl groups is disordered over two conformations: the occupancies of major components were fixed at 0.53 and 0.64 in the two mol-ecules. In the crystal structure, weak inter-molecular C-H⋯O hydrogen bonds link mol-ecules into chains propagating along [10].

Diethyl 2-[(3,5-dimethyl-1H-pyrazol-1-yl)(4-meth-oxy-phen-yl)meth-yl]propane-dioate.

The title compound, C(20)H(26)N(2)O(5), was prepared in good yield (76%) through condensation of diethyl (4-meth-oxy-benz-yl)propane-dioate with 3,5-dimethyl-1H-pyrazole. The dihedral between the benzene and pyrazole rings is 83.96 (10)°. The crystal packing is stabilized by a C-H⋯O inter-action, which links the mol-ecules into centrosymmetric dimers.

4-tert-Butyl-4'-(4-meth-oxy-phen-yl)-3'-(4-methyl-phen-yl)-1,2,3,4-tetra-hydro-spiro-[naphthalene-2,5'(4'H)-1,2-oxazol]-1-one.

In the title compound, C(30)H(31)NO(3), the tolyl ring is almost coplanar with the isoxazole ring [dihedral angle = 12.51 (7)°], whereas the meth-oxy-phenyl ring is almost perpendicular to the isoxazole ring [dihedral angle = 89.77 (5)°]. In the crystal, mol-ecules are connected through C-H⋯O hydrogen bonds, forming chains running along the a axis.

2-(4-Meth-oxy-benzyl-idene)-4,4-dimethyl-3,4-dihydro-naphthalen-1(2H)-one.

The title compound C(20)H(20)O(2), has the exocyclic C=C double bond in an E configuration. The two benzene rings form a dihedral angle of 72.92 (6)°.

Anti-tubercular activity of ruthenium (II) complexes with polypyridines.

A series of nine polypyridyl-ruthenium (II) complexes (N-ligands = 2,2'-bipyridines; 2,2'-6',2'-terpyridines, di-alkyloxy-2,2'-6,2-bipyridine-3,3'-di-carboxylates), were tested against Mycobacterium tuberculosis (MBT). The complex (11) showed remarkable activity against MBT as compared to other complexes, (1-10). The aquo ligand of complex (11), as opposed to other chloro and acetonitrile derivatives, appears to play a key role in the antitubercular potency of this new class of metal-based compounds.

4'-Methyl-3-(4-nitro-phen-yl)-4-phenyl-4,5,1',2',3',4'-hexa-hydro-spiro-[isoxazole-5,2'-naphthalen]-1'-one.

The title compound, C(25)H(20)N(2)O(4), is a new spiro-isoxazoline derivative. It contains a five-membered isoxazoline ring (A), a tetra-lone unit (E and D), a 4-nitro-phenyl substituent (B), and a phenyl ring (C). The isoxazoline ring (A) has an envelope conformation, while the cyclo-hexenone ring (D) has an inter-mediate sofa/half-chair conformation. The aromatic ring of the 4-nitro-phenyl substituent (B) is inclined at an angle of 78.97 (10)° to the phenyl ring (C). The rigid pharmacophore site, Osp(2)-C-C-Osp(3), is characterized by an O⋯O distance of 3.113 (2) Šand an O-C-C-O torsion angle of 97.8 (2)°. In the crystal structure, mol-ecules are linked by C-H⋯O contacts.

3,4-Bis(4-nitro-phen-yl)-1,2,5-oxadiazole 2-oxide.

The title compound, C(14)H(8)N(4)O(6), a new 1,2,5-oxadiazole N-oxide derivative, was formed by dimerization of 4-nitro-benz-al-de-hyde oxime. The compound crystallizes with two independent mol-ecules per asymmetric unit. The N-oxide O atom is disordered over two sites in each mol-ecule; site occupancy factors are 0.57/0.43 and 0.5/0.5. The mean planes through the two benzene rings are inclined to the planar 1,2,3-oxadiazole ring by 25.03 (11) and 41.64 (11)° in one mol-ecule, and 22.58 (11) and 42.66 (11)° in the other mol-ecule, the smaller angle being for the ring on the oxide side of the oxadiazole ring in each case. In the crystal structure, the individual mol-ecules form centrosymmetric dimers linked via C-H⋯O hydrogen bonds. The dimers of one mol-ecule are then linked to those of the other mol-ecule via C-H⋯O hydrogen bonds, forming a three-dimensional network.