1. Two polymorphs and the diethylammonium salt of the barbiturate eldoral
Thomas Gelbrich, Denise Rossi, Ulrich J Griesser Acta Crystallogr C. 2012 Feb;68(Pt 2):o65-70. doi: 10.1107/S0108270111055120. Epub 2012 Jan 6.
Polymorph (Ia) of eldoral [5-ethyl-5-(piperidin-1-yl)barbituric acid or 5-ethyl-5-(piperidin-1-yl)-1,3-diazinane-2,4,6-trione], C(11)H(17)N(3)O(3), displays a hydrogen-bonded layer structure parallel to (100). The piperidine N atom and the barbiturate carbonyl group in the 2-position are utilized in N-H···N and N-H···O=C hydrogen bonds, respectively. The structure of polymorph (Ib) contains pseudosymmetry elements. The two independent molecules of (Ib) are connected via N-H···O=C(4/6-position) and N-H···N(piperidine) hydrogen bonds to give a chain structure in the [100] direction. The hydrogen-bonded layers, parallel to (010), formed in the salt diethylammonium 5-ethyl-5-(piperidin-1-yl)barbiturate [or diethylammonium 5-ethyl-2,4,6-trioxo-5-(piperidin-1-yl)-1,3-diazinan-1-ide], C(4)H(12)N(+)·C(11)H(16)N(3)O(3)(-), (II), closely resemble the corresponding hydrogen-bonded structure in polymorph (Ia). Like many other 5,5-disubstituted derivatives of barbituric acid, polymorphs (Ia) and (Ib) contain the R(2)(2)(8) N-H···O=C hydrogen-bond motif. However, the overall hydrogen-bonded chain and layer structures of (Ia) and (Ib) are unique because of the involvement of the hydrogen-bond acceptor function in the piperidine group.
2. Di-ethyl-ammonium di-hydrogen orthophosphate
Peter Held Acta Crystallogr Sect E Struct Rep Online. 2014 Jan 11;70(Pt 2):o129. doi: 10.1107/S1600536814000464. eCollection 2014 Feb 1.
In the title molecular salt, [NH2(CH2CH3)2][H2PO4], two unique types of cations and anions, which are configurationally very similar, are present in the asymmetric unit. Both ions form sheets approximately parallel to (-1-1) linked by weak hydrogen bonds. The inter-connection within and between the sheets is reinforced by O-H⋯O and N-H⋯O hydrogen bonds involving the tetra-hedral H2PO4 anions and the ammonium groups.
3. NEW METHOD FOR THE SYNTHESIS OF AMMONIUM SALTS OF O,O'-ALKYLENEDITHIOPHOSPHORIC ACID AND OCTATHIOTETRAPHOSPHETANE. CRYSTAL STRUCTURE FEATURES'S OF DIETHYLAMMONIUM SALT OF O,O'-PROPYLENEDITHIOPHOSPHORIC ACID
Elena K Badeeva, Angelo Santomenna, Aidar T Gubaidullin, Liliya V Frolova, Snezna Rogelj, Elvira S Batyeva, Oleg G Sinyashin Phosphorus Sulfur Silicon Relat Elem. 2016;191(3):405-410. doi: 10.1080/10426507.2015.1091828. Epub 2016 Jan 14.
A new reaction of elemental phosphorus (P4) with elemental sulfur and 1,3-propylene glycol in the presence of different amines has been investigated. Ammonium salts of O,O'- alkylenedithiophosphoric acids have been observed as main products of the reaction. Octathiotetraphosphetane ammonium salts were formed as minor products. The reaction is characterized by a complete conversion of white phosphorus and is not accompanied by the release of hydrogen sulfide. The crystal structure features's of diethylammonium salt of O,O'-propylenedithiophosphoric acid were determined using single crystal X-ray diffraction. Piperidinium salt of octathiotetraphosphetane in DMSO and DMF solutions possess significant antifungal activity against Candida albicans.