Table 1.

Crystallographic data for 3a.

Empirical formula	C18 H10 N4 O•H2O
Formula weight	316.32
Crystal system	Monoclinic
Space group	P21/n
Temperature	173(2) K
Unit cell dimensions	a = 7.0829(12) (Å)
	b = 18.559(3) (Å)
	c = 11.0985(19)(Å)
	β = 107.736(2)0
Volume(Å3)	1389.6 (4)
Z	4
Densitycalc(Mg/m3)	1.512
Absorption coefficient	0.103 mm−1
Total data	15979
Unique data collected	3339
Observed data	2700
Internal agreement of data(Rint)	0.029
Number of parameters refined	217
Goodness of fit(S)	1.032
R 1	0.0592
wR 2	0.1653

$R_1=\sum \mid \mid F_0\mid -\mid F_c\mid \mid ∕\sum \mid F_0\mid$

${\mathit{wR}}_2={\{\sum \left[w{({F_o}^2-{F_c}^2)}^2\right]∕\sum \left[w{\left({F_o}^2\right)}^2\right]\}}^{1∕2}$