Structure of synephrine monohydrogenphosphate monohydrate

Abstract

Abstract2C9H14NO~-.HPOE-.H2 O, M r --450.4, monoclinic, P21/n, a = 12.108(4), b = 8.402(2), c = 21.549 (6)A, fl = 99.67 (3) °, Z = 4, D e = 1.384 Mg m -3, Cu Ka radiation, 2 = 1.54184 A,/z(Cu Ka) = 1.588 mm -I, V--2161.1A 3, F(000) = 960. The structure was solved by direct methods and refined by full-matrix least-squares calculations to a final R = 0.056 for 2562 uniquely observed diffractometer data with I > 2tr(I). The two molecules in the asymmetric unit exhibit different conformations, one of them being closely similar to other sympathomimetic amines including neo-and norsynephrine. The crystal structure is stabilized by a three-dimensional network of H bonds with p-hydroxyl and amino groups of the synephrine cations strongly bonded to O atoms of the phosphate anion, indicating a putative environment of these drug molecules at their receptor and storage sites in biological systems.

Mephentermine Hemisulfate Monohydrate: an Adrenergic Agent

“…The corresponding angles of 7-1 = -94.9(9) and 7-2 = 175.2(7) ° for molecule 1, and 7-1 = -91.7 (9) and 7-2 = -175.3 (8) ° for molecule 2, indicate that both molecules have a perpendicular trans conformation. A study of these torsion angles in other adrenergic agents like p-hydroxyephedrine hydrochloride (Dattagupta et al, 1981), synephrine monohydrogen phosphate monohydrate (Dattagupta et al, 1982), L-phenylephrine hydrochloride (Bhaduri et al, 1983), 2,2'-di-N-methylamino-1, l'-di-p-hydroxyphenyldiethylene ether dihydrobromide (Mukhopadhyay & Dattagupta, 1988) also show similar values. This indicates that a maximally extended ethylamine side chain approximately perpendicular to the benzene ring may be the receptor-preferred conformation for this class of drugs.…”

A β-Adrenergic Agonist: Protonated Terbutaline Hemisulfate

“…The distance of the amino-N atom from the centre of the benzene ring is 5.1 .~, in both of the molecules in the asymmetric unit. This distance seems to be fairly constant in similar biologically active amines like p-hydroxyephedrine hydrochloride (Dattagupta, Pattanayek & Saha, 1981), synephrine monohydrogenphosphate monohydrate (Dattagupta, Meyer & Mukhopadhyay, 1982), L-phenylephrine hydrochloride (Bhaduri, Saha, Dattagupta & Meyer, 1983), 2,2'-di-N-methylamino-1,1'-di-p-hydroxyphenyldiethylene ether dihydrobromide (Mukhopadhyay & Dattagupta, 1988) and also in ~-adrenergic agonists like salbutamol sulfate (Leger, Goursolle, Gadret & Carpy, 1978), Alupent and orciprenaline (Beale, 1972) and fenoterol hydrobromide (Dattagupta & Sengupta, 1995). This distance also appears to be of significance for sympathomimetic activity and may be important for drug-receptor interaction.…”