What is the Molecular Structure of an Indigo?

Question

How many covalent bonds are there?
How many single/double covalent bonds?

Answer 1

Indigo is a powder, insoluble in water, with a melting point higher than 300C. It absorbs light in the yellow region of the spectrum (maximum at 602 nm), which gives it its intense blue colour. The indigo molecule is relatively small with molecular weight of 262.27 atomic units of mass
9 covalent bonds,
9(C=C,C=O) double bonds,22(C-C,N-H,C-H) single bonds

Answer 2

http://www.indigopage.com/chemistry.htm
http://webexhibits.org/pigments/indiv/technical/indigo.html
http://en.wikipedia.org/wiki/Indigo_dye