Hydrothermal reaction of copper nitrate, a 5-position substituted isophthalic acid, and the long-spanning dipyridylamide ligand 1,6-hexanediaminebis(nicotinamide) (hbn) resulted in two new coordination polymers whose layer topologies and interpenetration mechanisms depend critically on the nature of the substituent. The new phases were structurally characterized by single crystal X-ray diffraction. {[Cu(meoip)(hbn)]center dot H2O)(n) (1, meoip = 5-methoxyisophthalate) exhibits [Cu(meoip)] chain motifs with embedded (Cu-2(OCO)(2)} dinuclear units, pillared by pairs of hbn ligands into a decorated (4,4) grid topology. {[Cu-3(sip)(2)(hbn)(3)(H2O)(4)]center dot 11.5H(2)O}(n) (2, sip = 5-sulfoisophthalate) displays neutral [Cu-3(si-P)(2)(H2O)(4)] fragments connected by hbn ligands into 3,4-connected layer motifs with a (4.6(2))(2){4(2)6(2)8(2)} topology, derived from the standard (4,4) grid with regular removal of some pillars. The layer motifs in 2 engage in 2D + 2D -> 3D parallel interpenetration, with entrained co-crystallized water molecule tapes. Thermal decomposition behavior of the new phases is also discussed. (C) 2017 Elsevier B.V. All rights reserved.