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Updated: Jun 1, 2026

A Direct, Early Stage Guanidinylation Protocol for the Synthesis of Complex Aminoguanidine-containing Natural Products
Published on: September 9, 2016
Tetra-guanidinium bis-[citrato(3-)]cuprate(II) dihydrate
Abstract:
The asymmetric unit of the title compound, (CH(6)N(3))(4)[Cu(C(6)H(5)O(7))(2)]·2H(2)O, contains one-half of a centrosymmetric Cu(II) complex anion, two guanidinium cations and a water mol-ecule. The Cu(II) ion, lying on a crystallographic inversion center, is hexa-coordinated with two citrate anions in a distorted octahedral geometry. An intra-molecular O-H⋯O hydrogen bond generates an S(6) ring motif. In the crystal structure, mol-ecules are linked into a three-dimensional framework by inter-molecular N-H⋯O and O-H⋯O hydrogen bonds.
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