Bermuda Triangle in Chemistry

It is believed that the place called Bermuda triangle is able to hide of human seeing objects entered its area. A Bermuda triangle in chemistry is able to hide (mask) atoms or planar molecular fragments cut by their mirror plane of symmetry, not of human eyes but, of polarized light. A triangular skeleton (frame) has been imagined, possessing the ability to cover many hundreds of molecular formulae, providing the latter refer to aliphatic, or partially aliphatic, compounds, and with a low degree of oxidation. This skeleton (frame) is based on a very general and strong principle, valid in meso entities. The idea is advanced that isomers coming up from a molecular formula could be of four types (groups): meso, C2 symmetrical (CTS), irrechi (from irregular chiral) and constitutional (constit.). The following universal rule is revealed: all CTS and irrechi can be converted to meso ones, but the reverse is not true, at least for the same skeleton. At the same time, an impressive number of constitutional natural or synthetic combinations are characterized by at least one real or envisaged meso isomer. Thus, from a structural point of view, meso isomers are justified as reference compounds. The above mentioned principles have been applied to numerous natural compounds: amino acids, lipids, carbohydrates, nucleosides, vitamins, steroids, alkaloids, hydrocarbons. A mathematical equation sustaining the triangular representation has been proposed. One raises the question which of the four types is the upper. A tentative answer is given to this question.