The main aim of nanotechnology is to create functional systems by controlling the matter at the nano-meter level. In this context DNA is a versatile building block for the fabrication of micrometer-scale objects with a subnanometer-scale resolution. Over the last 15 years, DNA nanotechnology has considerably developed with the invention of DNA origami, double crossover structures and molecule/ oligonucleotide hybrids. Our interest is focused on the combination of short complementary DNA sequences with organic molecules with a view to create large self-assembled nanostructures. Here we report on the synthesis of porphyrin derivatives bearing up to four 21-mer oligonucleotides and we demonstrate that the combination of the molecular hybrids containing complementary DNA strands leads to the formation of large nanostructures with micrometer-scale size.