The title compound, C12H1609N2. H20, F.W. 332"3, crystallizes with a= 11.159 (2), b= 14.461 (2), c= 4-821 (1) A, fl=101-15 (2) °, U=763.2 ,~3, Dx= 1.45 g cm -a and space group P21, Z=2. The crystal structure was refined to an R value of 0.04 for 1332 observed reflexions including 13 hydrogen atoms out of 18. The conformation of the sugar moiety is C(3')-endo with Z=34.3 ° (anti), ~0oo = -58.7 and tPoc = 58.8 ° (gg). The bases are stacked along the c axis but are tilted by 46o42 ' relative to the c axis.No direct hydrogen bonds are found between the bases. ExperimentalCrystals were grown by slow evaporation of a methanol solution of uridine-5-oxyacetic acid at 50°C. Platelike crystals of the methyl ester appeared in about a week. The lattice constants and the intensity data were measured on a Rigaku four-circle diffractometer using Ni-filtered Cu Kc~ radiation. Intensities of reflexions with 20 values up to 135 ° were collected by the 0-20 scan method with a scan rate of 20 2 ° rain -t. Background was measured at each end of the scan for 10 s. The size of the crystal was about 0.1 x 0.25 x 0.7 mm. The intensities were corrected for Lorentz and polarization factors and were then converted to normalized structure factors. The total number of independent observed reflexions above the 2a level was 1332 out of 1356 theoretically possible reflexions.Attempts at determination of the crystal structure by direct methods gave no conclusive result. The Patterson map, on the other hand, gave the orientation of a hexagonal pyrimidine nucleus along with two substituent atoms at the para positions lying in the plane. The structure factors for the hOl reflexions were therefore calculated by assuming the disposition of eight atoms which may form a 1,4-disubstituted pyrimidine base. A two-dimensional R map was then calculated by translating these atoms together along the a and c axes. The most probable x and z coordinates of an arbitrarily chosen origin fixed to the atomic group could be found on the R map. The y coordinate was chosen arbitrarily. More precise values of x and z were determined by searching the lowest R values near the position obtained above, but in this case the structure factors of all hkl reflexions were taken into account.

A novel chiral polyimine macrocycle C‐1 was designed and synthesized by the self‐condensation of the dialdehyde of the chiral dinaphtho[2,1‐d:1′,2′‐f][1,3]dioxepine derivative and o‐phenylenediamine by Schiff base formation, and the corresponding polyamine macrocycle C‐1H was obtained by the reduction of the polyimine macrocycle. The UV–vis and fluorescence spectral studies indicated that both C‐1 and C‐1H form the complex with metal ions in a 1:2 ratio. The fluorescence behaviour of C‐1 upon the addition of Zn2+ or Cd2+ showed a ‘turn‐on’ response accompanied by fluorescence enhancement at 510 nm six times for Cd2+ and 13 times for Zn2+. In contrast, C‐1H revealed a ‘turn‐off’ response upon the addition of Co2+, Ni2+, and Cu2+.

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