Different cationic forms of (–)-cytisine in the crystal structures of its simple inorganic salts

2018 ◽  
Vol 74 (11) ◽  
pp. 1518-1530 ◽  
Author(s):  
Agata Owczarzak ◽  
Anna K. Przybył ◽  
Maciej Kubicki

The crystal structures of 13 simple salts of cytisine, an alkaloid isolated from the seeds of Laburnum anagyroides, have been determined, namely cytisinium (6-oxo-7,11-diazatricyclo[7.3.1.02,7]trideca-2,4-dien-11-ium) bromide, C11H15N2O+·Br−, cytisinium iodide, C11H15N2O+·I−, cytisinium perchlorate, C11H15N2O+·ClO4 −, cytisinium iodide triiodide, C11H15N2O+·I−·I3 −, cytisinium chloride monohydrate, C11H15N2O+·Cl−·H2O, cytisinium iodide monohydrate, C11H15N2O+·I−·H2O, cytisinium nitrate monohydrate, C11H15N2O+·NO3 −·H2O, hydrogen dicytisinium tribromide, C22H31N4O2 3+·3Br−, hydrogen dicytisinium triiodide, C22H31N4O2 3+·3I−, hydrogen dicytisinium triiodide diiodide, C22H31N4O2 3+·I3 −·2I−, hydrogen dicytisinium bis(triiodide) iodide, C22H31N4O2 3+·2I3 −·I−, cytisinediium (6-oxidaniumylidene-7,11-diazatricyclo[7.3.1.02,7]trideca-2,4-dien-11-ium) bis(perchlorate), C11H16N2O2+·2ClO4 −, and cytisinediium dichloride trihydrate, C11H16N2O2+·2Cl−·3H2O. Cytisine has two potential protonation sites, i.e. the N atom of the piperidine ring and the carbonyl O atom of the pyridone ring. Three forms of the cytisinium cation were identified, namely the monocation, which is always protonated at the N atom, the dication, which utilizes both protonation sites, and the third form, which contains two cytisine moieties connected by very short and linear O...H...O hydrogen bonds, with an O...O distance of approximately 2.4 Å. This third form may therefore be regarded as a 3+ species, or sesqui-cation, and is observed solely in the salts with bromide, iodide or triiodide (heavier halogen) anions. The cation is quite rigid and all 19 cytisinium fragments in the studied series have very similar conformations. The crystal structures are determined mainly by Coulombic interactions and hydrogen bonds, and the latter form is determined by different networks. Additionally, some anion–π and lone-pair...π secondary interactions are identified in almost all of the crystal structures. Hirshfeld surface analysis generally confirms the role of different interactions in the determination of the crystal architecture.

2018 ◽  
Vol 74 (8) ◽  
pp. 1111-1116 ◽  
Author(s):  
Shet M. Prakash ◽  
S. Naveen ◽  
N. K. Lokanath ◽  
P. A. Suchetan ◽  
Ismail Warad

2-Aminopyridine and citric acid mixed in 1:1 and 3:1 ratios in ethanol yielded crystals of two 2-aminopyridinium citrate salts, viz. C5H7N2 +·C6H7O7 − (I) (systematic name: 2-aminopyridin-1-ium 3-carboxy-2-carboxymethyl-2-hydroxypropanoate), and 3C5H7N2 +·C6H5O7 3− (II) [systematic name: tris(2-aminopyridin-1-ium) 2-hydroxypropane-1,2,3-tricarboxylate]. The supramolecular synthons present are analysed and their effect upon the crystal packing is presented in the context of crystal engineering. Salt I is formed by the protonation of the pyridine N atom and deprotonation of the central carboxylic group of citric acid, while in II all three carboxylic groups of the acid are deprotonated and the charges are compensated for by three 2-aminopyridinium cations. In both structures, a complex supramolecular three-dimensional architecture is formed. In I, the supramolecular aggregation results from Namino—H...Oacid, Oacid...H—Oacid, Oalcohol—H...Oacid, Namino—H...Oalcohol, Npy—H...Oalcohol and Car—H...Oacid interactions. The molecular conformation of the citrate ion (CA3−) in II is stabilized by an intramolecular Oalcohol—H...Oacid hydrogen bond that encloses an S(6) ring motif. The complex three-dimensional structure of II features Namino—H...Oacid, Npy—H...Oacid and several Car—H...Oacid hydrogen bonds. In the crystal of I, the common charge-assisted 2-aminopyridinium–carboxylate heterosynthon exhibited in many 2-aminopyridinium carboxylates is not observed, instead chains of N—H...O hydrogen bonds and hetero O—H...O dimers are formed. In the crystal of II, the 2-aminopyridinium–carboxylate heterosynthon is sustained, while hetero O—H...O dimers are not observed. The crystal structures of both salts display a variety of hydrogen bonds as almost all of the hydrogen-bond donors and acceptors present are involved in hydrogen bonding.


CrystEngComm ◽  
2014 ◽  
Vol 16 (28) ◽  
pp. 6398-6407 ◽  
Author(s):  
Julio Zukerman-Schpector ◽  
Edward R. T. Tiekink

DMSO-O(lone pair)⋯π(arene), DMSO-S(lone pair)⋯π(arene) and SO⋯π(arene) interactions are found in DMSO solvates.


2000 ◽  
Vol 24 (3) ◽  
pp. 143-147 ◽  
Author(s):  
Venkat R. Thalladi ◽  
Tanja Smolka ◽  
Annette Gehrke ◽  
Roland Boese ◽  
Reiner Sustmann

2014 ◽  
Vol 70 (10) ◽  
pp. 199-202 ◽  
Author(s):  
B. Raghuvarman ◽  
R. Sivakumar ◽  
V. Thanikachalam ◽  
S. Aravindhan

In the title compounds, C27H28N2O3, (I), and C28H30N2O3, (II), the conformation about the C=N bond isE. The piperidine rings adopt chair conformations with the attached phenyl rings almost normal to their mean planes, the dihedral angles being 85.82 (8) and 85.84 (7)° in (I), and 87.98 (12) and 86.42 (13)° in (II). The phenyl rings are inclined to one another by 52.87 (8)° in (I) and by 60.51 (14)° in (II). The main difference in the conformation of the two compounds is the angle of inclination of the phenoxycarbonyl ring to the piperidine ring mean plane. In (I), these two planes are almost coplanar, with a dihedral angle of 2.05 (8)°, while in (II), this angle is 45.24 (13)°. In the crystal of (I), molecules are linked by C—H...O hydrogen bonds, forming inversion dimers withR22(14) loops. The dimers are linkedviaC—H...π interactions forming a three-dimensional network. In the crystal of (II), there are no significant intermolecular interactions present.


Author(s):  
E. Mesto ◽  
E. Quaranta

The crystal structures of 8-phenoxycarbonyl-1,8-diazabicyclo[5.4.0]undec-7-enium chloride, C16H21N2O2+·Cl−, (I), and 8-methoxycarbonyl-1,8-diazabicyclo[5.4.0]undec-7-enium chloride monohydrate, C11H19N2O2+·Cl−·H2O, (II), recently reported by Carafa, Mesto & Quaranta [Eur. J. Org. Chem.(2011), pp. 2458–2465], are analysed and discussed with a focus on crystal interaction assembly. Both compounds crystallize in the space groupP21/c. The crystal packings are characterized by dimers linked through π–π stacking interactions and intermolecular nonclassical hydrogen bonds, respectively. Additional intermolecular C—H...Cl interactions [in (I) and (II)] and classical O—H...Cl hydrogen bonds [in (II)] are also evident and contribute to generating three-dimensional hydrogen-bonded networks.


2021 ◽  
Vol 23 (102) ◽  
pp. 53-59
Author(s):  
M. D. Kukhtyn ◽  
Y. V. Horiuk ◽  
V. Z. Salata ◽  
V. T. Klymyk ◽  
N. M. Vorozhbit ◽  
...  

The presence of Staphylococcus aureus in raw milk is considered a direct danger to consumers. Almost all types of dairy products normalize the amount of Staphylococcus aureus in 1 g (cm3) of product, due to their ability to produce thermostable enterotoxins. The aim of the study was to investigate the role of incision of teats of healthy and sick mastitis cows and milking equipment for irradiation of cow's milk with Staphylococcus aureus. Sanitation of milking equipment in farms was carried out with alkaline detergents based on sodium hypochlorite and acid based on phosphoric acid. Blood agar with 5 % sodium chloride was used to isolate staphylococci from washes and milk. Species identification of pure cultures of staphylococci was performed using RapID Staph Plus kits. At the same time before and after milking the skin of teats with Udder Wash and Udder Forte reduces the incidence of Staphylococcus aureus to 4.1 ± 0.3 % of cases. Quantitative determination of staphylococci, including golden on the skin of the teats revealed a decrease in the latter from 283.5 ± 21.2 to 27.6 ± 2.1 CFU/cm3 flush after milking. It has been established that the number of staphylococci, including golden, on the skin of teats increases sharply under subclinical or clinical ointment. Thus, it was found that in the subclinical form of staphylococcal mastitis from the skin of teats isolated S. aureus in the amount of 790.6 ± 65.4 CFU/cm3 of wash. At the same time, in the clinical form of mastitis, the amount of S. aureus increased, on average to 8 thousand CFU/cm3 of flush. It was found that under the condition of sanitary treatment of milking equipment with alternate use of alkaline and acid detergents and disinfectants, only 25 % of washes were staphylococci, and gold – up to 5 % of samples. It was found that in 43.7 ± 3.9 % of raw milk samples Staphylococcus aureus was not detected in 1 cm3. The number of milk samples containing Staphylococcus aureus up to 100 CFU/cm3 was 39.1 ± 3.3 %, and 17.2 ± 1.4 % of milk samples were contaminated with Staphylococcus aureus in the amount of 101 to 200 CFU/cm3. Therefore, the presence of more than 200 CFU/cm3 in freshly milked Staphylococcus aureus in milk indicates the ineffectiveness of antimastitis measures, skin remediation of teats and sanitation of milking equipment.


2000 ◽  
Vol 55 (11) ◽  
pp. 1089-1094 ◽  
Author(s):  
Irena Wolska ◽  
Franciszek Herold

The X-ray crystal structure determination of 4-(4'-fluorophenyl)hexahydro-1H,3H-pyrido[ 1,2-c]pyrimidine-1,3-dione (5) and 4-(4'-chlorophenyl)hexahydro-1H,3H-pyrido [1,2-c]- pyrimidine-1,3-dione (8) is reported. The crystal structures show the formation of centrosymmetric dimers via intermolecular N-H···O hydrogen bonds. The saturated ring adopts a slightly distorted sofa conformation both in 5 and in 8. In either compound the planar phenyl ring is twisted with respect to the pyrimidine-1,3-dione fragment.


2020 ◽  
Vol 76 (6) ◽  
pp. 562-571 ◽  
Author(s):  
Levi Senior ◽  
Anthony Linden

The crystal structures of six halobismuth(III) salts of variously substituted aminopyridinium cations display discrete mononuclear [BiCl6]3− and dinuclear [Bi2 X 10]4− anions (X = Cl or Br), and polymeric cis-double-halo-bridged [Bi nX 4 n ] n− anionic chains (X = Br or I). Bis(2-amino-3-ammoniopyridinium) hexachloridobismuth(III) chloride monohydrate, (C5H9N3)2[BiCl6]Cl·H2O, (1), contains discrete mononuclear [BiCl6]3− and chloride anions. Tetrakis(2-amino-3-methylpyridinium) di-μ-chlorido-bis[tetrachloridobismuth(III)], (C6H9N2)4[Bi2Cl10], (2), tetrakis(2-amino-3-methylpyridinium) di-μ-bromido-bis[tetrabromidobismuth(III)], (C6H9N2)4[Bi2Br10], (3), and bis(4-amino-3-ammoniopyridinium) di-μ-chlorido-bis[tetrachloridobismuth(III)] dihydrate, (C5H9N3)2[Bi2Cl10]·2H2O, (4), incorporate discrete [Bi2 X 10]4− anions (X = Cl or Br), while catena-poly[2,6-diaminopyridinium [[cis-diiodidobismuth(III)]-di-μ-iodido]], {(C5H8N3)[BiI4]} n , (5), and catena-poly[2,6-diaminopyridinium [[cis-dibromidobismuth(III)]-di-μ-bromido]], {(C5H7N2)[BiBr4]} n , (6), include [Bi nX 4 n ] n− anionic chains (X = Br or I). Structures (2) and (3) are isostructural, while that of (5) is a pseudomerohedral twin. There is no discernible correlation between the type of anionic species obtained and the cation or halide ligand used. The BiIII centres always have a slightly distorted octahedral geometry and there is a correlation between the Bi—X bond lengths and the number of classic N—H...X hydrogen bonds that the X ligand accepts, with a greater number of interactions corresponding with slightly longer Bi—X distances. The supramolecular networks formed by classic N—H...X hydrogen bonds include ladders, bilayers and three-dimensional frameworks.


Sign in / Sign up

Export Citation Format

Share Document