A porous anionic framework with cubic symmetry and multi-intersecting open channels, {[H(2)tmdp](3)[In-6(btc)(8)]center dot 40H(2)O}(n) (1) (tmdp= 4,4'-trimethylene dipiperidine, H(3)btc=1,3,5-benzenetricarboxylic acid), is reported. Complex 1 crystallizes in the cubic space group I (4) over bar 3d (a = b = c = 20.3732(g) angstrom, V = 8456.2(6) angstrom(3), and Z = 2). Its cagelike units, Ing(btc)(11), constitute a large accessible void with 65.4% of the total volume. The cationic guests located in the channels can be exchanged with inorganic ions, such as K+, NH4+, Ca2+, Sr2+, and Ba2+.