The microscopic magnetic local structure of Botallackite-type layer-structured compounds Cu-2(OD)(3)X (X = C6H5COO-) exhibiting a nonequilateral planar triangular copper lattice was determined by the solid-state high-resolution deuterium NMR above 190 K. The magnetic interaction in a copper layer was probed by the isotropic NMR shifts of OD- groups and could be approximated by a sum of 1D-Heisenberg chains in the high temperature region. Two copper chains with different exchange interactions J = -54 +/- 4 and -92 +/- 3 K were found for Cu-2(OD)(3)C6H5COO from the temperature dependence of the three distinct NMR signals. The derived values of J almost reproduced the high temperature behavior of the magnetic susceptibility chi(A)T vs. T. The magnetic susceptibility of isotopic analogue Cu-2(OH)(3)C6D5COO showed ferromagnetic interaction below 50 K. Electron spin distribution in a phenyl ring of a benzoate anion is governed by spin polarization mechanism and it's magnitude is very small. Magnetic interaction between the layers through the benzoate anion is very weak.