4-Sulfamoylanilinium nitrate

In the crystal structure of the title compound, C6H9N2O2S+·NO3 −, the cations and anions are connected by N—H⋯O hydrogen bonds into a three-dimensional network.


SPR and BRK thank the management of the Devanga Arts
College for their support and encouragement and also extend their thanks to the University Grants Commission for the financial support of this work in the form of a Minor Research Project.
Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: BT5645). an enzyme involved in folate synthesis which involves para-aminobenzoic acid (PABA). PABA is needed in enzymatic reactions that produce folic acid which acts as a coenzyme in the synthesis of purine, pyrimidine and other amino acids (Kent, 2000). Sulfonamide drugs were the first antimicrobial drugs, and paved the way for the antibiotic revolution in medicine.

Structure Reports Online
The antibacterial activity of sulfanilamide, was first investigated by Buttle (Buttle et al., 1936). The use of sulfanilamide was eclipsed by its prodrugs, the more effective sulfadrugs, shortly afterwards. From literature, it is observed that sulfadrugs are remarkably polymorphic. The polymorphs of sulfathiazole (Hughes et al., 1999) and sulfapyridine (Gelbrich et al., 2007) were already reported. The polymorphism of sulfanilamide was extensively investigated over a number of years (Burger, 1973). There are three well known polymorphs, usually represented as α, β and γ sulfanilamides (Alléaume & Decap, 1965a,b;O'Connor & Maslen, 1965;O'Connell & Maslen, 1967). Based on the above specifics, we are interested on the investigation of hydrogen bonding tendancy and its reactivity with different inorganic/organic acids.
The crystal structure is stabilized through intricate three dimensional hydrogen bonding network formed through N-H···O hydrogen bonds (Fig 2, Table 1). The N atom of the -NH 2 group of the cation is hydrogen bonded with O atom of the S=O group making a zigzag chain C(4) motif extending along c axis of the unit cell (Etter et al., 1990). Further, the N atom of the -NH 3 group of the cation is hydrogen bonded with another O atom of the S=O group making a head-to-tail like chain C(8) motif extending along diagonal of the ab-plane. Nitrate anions are sandwiched between these two chains leading to a unusual asymmetric ring R 5 5 (16) motif which involves four cation and one anion. Also, cations are linked through anion by two N-H···O hydrogen bonds [viz., N1-H1B···O4 (x, 1 -y, 1/2 + z) and N2-H3N···O5 (-1/2 + x, 3/2 -y, -1/2 + z)] forming a chain C 2 2 (12)motif extending along diagonal of the bc-plane.

Experimental
Colourless crystals of 4-sulfamoylanilinium nitrate suitable for single-crystal X-ray analysis were obtained by slow evaporation at room temperature from an aqeuous solution of sulphanilamide and nitric acid.

Refinement
The H atoms bonded to N located were refined istropically. All other H atoms were positioned geometrically and refined by the riding model approximation with d(C-H) = 0.93 Å and U iso (H)= 1.2 U eq (C). Fig. 1. The molecular structure of the title compound with atom numbering scheme and 50% probability displacement ellipsoids.  Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > σ(F 2 ) is used only for calculating Rfactors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.