Studies on pyran,its analogs,and related compounds

The action of guanidine on esters of chromone-2-carboxylic acids leads to the opening of the pyrone ring and to the formation of hydantoin derivatives — 2-imino-5-(2-hydroxybenzoylmethylene)tetrahydroimidazol-4-ones — in addition to other reaction products.Translated from Khimiya Geterotsiklicheskikh Soedinenii, Vol. 6, No. 7, pp. 874–875, July, 1970.     

Chiral symmetry restoration in hadron spectra

The evidence and the theoretical justification of chiral symmetry restoration in high-lying hadrons is presented.     

Chiral symmetry restoration in excited hadrons and dense matter

We overview two interconnected topics: possible effective restoration of chiral symmetry in highly excited hadrons and possible existence of confined but chirally symmetric matter at low temperatures and high densities.     

Chiral symmetry restoration in excited hadrons and dense matter

We overview two interconnected topics： possible effective restoration of chiral symmetry in highly excited hadrons and possible existence of confined but chirally symmetric matter at low temperatures and high densities.     

Synthesis and properties of 2-amino-1-thio-4-chromone derivatives

2-Amino-1-thio-4-chromone was synthesized and its substitution reactions at the N and C₃ atoms were studied. The mass spectrometric behavior of the synthesized 2-amino-1-thio-4-chromone derivatives was studied.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 182–185, February, 1978.     

A study of the Li(π, pp)He reaction within the three-body problem

The differential cross section for the ⁶Li(π⁺, pp)⁴He reaction for symmetrical coplanar kinematics has been calculated at the incident pion energy E_π = 70 MeV within the three-body problem + 2N taking into account the Pauli exclusion principle in each N subsystem. Three-body distortions in the final state have been taken into account in the eikonal approximation. The treatment is based on the superposition of the single-particle and two-particle mechanisms of absorption leading to the rescattering of the π- and ρ-mesons through the Δ-isobar. The analytical character of the adopted wave function for the ⁶Li nucleus (the multidimensional gaussian basis) makes it possible to ascertain clearly that the reaction amplitude of the type under study is insensitive to short-range NN correlations both in the initial and final states. The calculated momentum distribution of recoil -particles is in good agreement with the experimental data available, but the experimental accuracy should be improved in order to see the contribution of a specific three-body part of the ⁶Li wave function orthogonal to the ad channel. Some problems to be solved in future are discussed.     

Reactions and mass-spectrometric study of aza analogs of 2-aminochromone

Electrophilic substitution reactions at the C and N(₂) atoms of 2-amino-4-oxo-4H-pyrano[2,3-b]pyridine were studied, 2-Aminoazachromones were subjected to a massspectroscopic study in comparison with 2-aminochromenes, and fundamental differences in their fragmentation were established.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1477–1483, November, 1976.