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1.
Chirality ; 36(6): e23680, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38771563

ABSTRACT

Truxillines are a group of tropane alkaloids present in coca leaves that are formed by photochemical dimerization of cinnamoylcocaine(s). Proportion of different truxilline forms present in cocaine serves as its geographical, manufacture, and storage "fingerprint"; thus, the quantitative determination of truxilline content represents one of the powerful methods of analysis and characterization of cocaine samples. Contrary to the statements repeatedly presented in the literature, namely, that there exist exactly 11 truxillines and that every single truxilline is diastereomer of any other, here we show that, in fact, a total of 15 truxillines exist, which can be divided in two structurally isomeric groups-five mutually diastereomeric truxillates and 10 mutually diastereomeric truxinates.


Subject(s)
Tropanes , Stereoisomerism , Tropanes/chemistry , Cocaine/chemistry , Cocaine/analysis , Alkaloids/chemistry
2.
RSC Adv ; 10(29): 17070-17078, 2020 Apr 29.
Article in English | MEDLINE | ID: mdl-35496933

ABSTRACT

Supramolecular ionogels composed of an ionic liquid (IL) immobilized in a network of self-assembled low-molecular weight molecules have been attracting considerable interest due to their applicability as smart electrolytes for various electrochemical applications. Despite considerable scientific effort in this field, the design of a mechanically and thermally stable yet highly conductive supramolecular ionogels still remains a challenge. In this article, we report on a series of novel ionogels of three ILs containing different cations (imidazolium/pyrrolidinium) and anions (tetrafluoroborate/bis(trifluoromethylsulfonyl)imide) prepared using (S,S)-bis(amino alcohol)oxamides as gelators. The gelation behaviour of the oxamide compound depends strongly on the structural features of amino alcohol substituents. Among them, (S,S)-bis(valinol)oxamide (capable of gelling all three ILs) and (S,S)-bis(phenylalaninol)oxamide (capable of gelling ILs based on bis(trifluoromethylsulfonyl)imide with a concentration as low as ≈0.2 wt%) are highly efficient. All investigated supramolecular ionogels retain the high ionic conductivity and ion diffusion coefficients of their parent IL, even for high gelator concentrations. Further, at low temperatures we observe an enhancement of the ionic conductivity in ionogels of (i) 1-butyl-3-methylimidazolium tetrafluoroborate which can be attributed to specific interactions between ionic species and gelator molecules and (ii) 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide due to inhibited crystallization. In contrast to ionic transport, mechanical strength of the ionogels shows a wider variation depending on the type and concentration of the oxamide gelator. Among all the ionogels, that of 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide prepared with 1 wt% (S,S)-bis(phenylalaninol)oxamide exhibits the best performance: optical transparency, stability over a wide temperature range, high conductivity and high mechanical strength. The results presented here reveal the versatile nature of bis(amino alcohol)oxamides as gelators and their high potential for preparing functionalized IL-based materials.

4.
Molecules ; 23(12)2018 Nov 30.
Article in English | MEDLINE | ID: mdl-30513686

ABSTRACT

Mechanochemical ball milling catalytic transfer hydrogenation (CTH) of aromatic nitro compounds using readily available and cheap ammonium formate as the hydrogen source is demonstrated as a simple, facile and clean approach for the synthesis of substituted anilines and selected pharmaceutically relevant compounds. The scope of mechanochemical CTH is broad, as the reduction conditions tolerate various functionalities, for example nitro, amino, hydroxy, carbonyl, amide, urea, amino acid and heterocyclic. The presented methodology was also successfully integrated with other types of chemical reactions previously carried out mechanochemically, such as amide bond formation by coupling amines with acyl chlorides or anhydrides and click-type coupling reactions between amines and iso(thio)cyanates. In this way, we showed that active pharmaceutical ingredients Procainamide and Paracetamol could be synthesized from the respective nitro-precursors on milligram and gram scale in excellent isolated yields.


Subject(s)
Hydrocarbons, Aromatic/chemistry , Nitro Compounds/chemistry , Aniline Compounds/chemistry , Catalysis , Hydrogenation , Spectroscopy, Fourier Transform Infrared
5.
Chem Commun (Camb) ; 48(99): 12100-2, 2012 Dec 25.
Article in English | MEDLINE | ID: mdl-23135220

ABSTRACT

Environmentally friendly one-pot synthesis of amides, bis-amides and dipeptides by mechanochemical carbodiimide-mediated coupling of carboxylic acids and amines is described; high reaction yields and simple aqueous work-up allow for the clean, practical and fast preparation of a variety of compounds containing the amide bond from readily accessible reagents.


Subject(s)
Amides/chemistry , Amines/chemistry , Carboxylic Acids/chemistry , Dipeptides/chemistry , Amides/chemical synthesis , Carbodiimides/chemistry , Water/chemistry
6.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 7): o2152, 2012 Jul 01.
Article in English | MEDLINE | ID: mdl-22798825

ABSTRACT

The cation of the title compound, C(14)H(15)N(2)O(2) (+)·Cl(-), comprises two almost ideally planar systems, 3-nitro-phenyl (r.m.s. deviation = 0.0117 Å) and 4-methyl-phenyl (r.m.s. deviation = 0.238 Å), separated by the central C-N bond, and with their mean planes inclined to one another by 61.36 (5)°. In the crystal, hydrogen-bonded chains running along [001] are generated by connecting neighbouring mol-ecules via N-H⋯Cl hydrogen bonds and consolidated by C-H⋯Cl and C-H⋯O inter-actions. Within these chains, fused R(2) (1)(6) and R(3) (2)(10) ring motifs are formed. Parallel chains are further linked into a two-dimensional network parallel to (100) via C-H⋯O inter-actions.

7.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 6): o1967, 2012 Jun 01.
Article in English | MEDLINE | ID: mdl-22719713

ABSTRACT

In the title compound, C(14)H(14)N(2)O(2), the angle between the mean plane of the N-methyl-3-nitro-aniline system (r.m.s. deviation = 0.0185 Å) and the p-tolyl unit is 89.79 (4)°. In the crystal, hydrogen-bonded chains running along [10-1] are generated by the linking of neighbouring mol-ecules via N-H⋯O and C-H⋯O hydrogen bonds involving the 3-nitro-aniline systems and forming R(2) (2)(8) motifs.

8.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 11): o3013, 2011 Nov.
Article in English | MEDLINE | ID: mdl-22220030

ABSTRACT

The mol-ecule of the title compound, C(13)H(12)N(2)O(2), has a bent conformation with a torsion angle about the central C-N bond of 72.55 (19)°. In the crystal, the mol-ecules are connected via classical N-H⋯O and non-classical C-H⋯O hydrogen bonds into chains along [10[Formula: see text]]. The dihedral angle between the ring planes is 86.0 (6)°.

9.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 5): o774-5, 2008 Apr 02.
Article in English | MEDLINE | ID: mdl-21202268

ABSTRACT

The asymmetric unit of the title compound, C(12)H(24)N(+)·C(8)H(7)O(3) (-), contains one dicyclo-hexyl-ammonium cation and one 2-methoxy-benzoate anion. Two cations and two anions are linked together to form a four-ion cluster through a set of N-H⋯O hydrogen bonds. Weak C-H⋯O hydrogen bonds connect the clusters into chains that are stacked along the crystallographic c axis.

10.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 1): o262, 2007 Dec 12.
Article in English | MEDLINE | ID: mdl-21200827

ABSTRACT

The V-shaped propeller-like mol-ecule of the title compound, C(29)H(24)O(4), does not exhibit crystallographic twofold symmetry as the two benzene rings are twisted asymmetrically with respect to both the central propyl plane and the benzo-yloxy groups [4.6 (2), 43.6 (2)° and 45.07 (8), 69.50 (8)°]. In the crystal structure, centrosymmetrically related mol-ecules form a dimer through C-H⋯π inter-molecular inter-actions.

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