Quantum mechanics with a time-dependent random unitary Hamiltonian: A perturbative study of the nonlinear Keldysh sigma-model

We analyze the perturbative series of the Keldysh-type sigma-model proposed recently for describing the quantum mechanics with time-dependent Hamiltonians from the unitary Wigner-Dyson random-matrix ensemble. We observe that vertices of orders higher than four cancel, which allows us to reduce the calculation of the energy-diffusion constant to that in a special kind of the matrix \phi^4 model. We further verify that the perturbative four-loop correction to the energy-diffusion constant in the high-velocity limit cancels, in agreement with the conjecture of one of the authors.Comment: 27 pages, 15 figures; typos corrected, one reference adde

Weak Charge Quantization on Superconducting Islands

We consider the Coulomb blockade on a superconductive quantum dot strongly coupled to a lead through a tunnelling barrier and/or normal diffusive metal. Andreev transport of the correlated pairs leads to quantum fluctuations of the charge on the dot. These fluctuations result in exponential renormalization of the effective charging energy. We employ two complimentary ways to approach the problem, leading to the coinciding results: the instanton and the functional RG treatment of the non-linear sigma model. We also derive the charging energy renormalization in terms of arbitrary transmission matrix of the multi-channel interface.Comment: 21 pages, 4 eps figures, RevTe

A General Synthetic Route to Isomeric Pyrrolo[1,2- x][1,4]diazepinones

A simple one-pot method for the synthesis of isomeric pyrrolo[1,2-x][1,4]diazepinones in reasonable yields was developed. The method is based on the condensation of readily available N-Boc amino acids with biomass-derived furans containing aminoalkyl groups followed by deprotection, furan ring opening, and Paal-Knorr cyclization. Using this approach, we synthesized pyrrolo[1,2-a][1,4]diazepin-3(2H)-ones from furfurylamines and β-amino acids and pyrrolo[1,2-d][1,4]diazepin-4(5H)-ones from 2-(2-furyl)ethylamines and α-amino acids. The cytotoxicity of the synthesized pyrrolodiazepinones was studied. © 2018 American Chemical Society

A Straightforward Approach to Tetrahydroindolo[3,2-b]carbazoles and 1-Indolyltetrahydrocarbazoles through [3+3] Cyclodimerization of Indole-Derived Cyclopropanes

Dimerization is among the most challenging and fascinating reactions that, within one step, can provide a significant increase in structural complexity in a highly stereoselective manner. Indole-containing donor-acceptor cyclopropanes are appropriate candidates for dimerization reactions that provide rapid accesses to various biologically active bis-indole compounds. More information can be found in the Communication by E.M. Budynina, et al. (DOI: 10.1002/chem.201502287). © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

A General Synthetic Route to Isomeric Pyrrolo[1,2- x][1,4]diazepinones

A simple one-pot method for the synthesis of isomeric pyrrolo[1,2-x][1,4]diazepinones in reasonable yields was developed. The method is based on the condensation of readily available N-Boc amino acids with biomass-derived furans containing aminoalkyl groups followed by deprotection, furan ring opening, and Paal-Knorr cyclization. Using this approach, we synthesized pyrrolo[1,2-a][1,4]diazepin-3(2H)-ones from furfurylamines and β-amino acids and pyrrolo[1,2-d][1,4]diazepin-4(5H)-ones from 2-(2-furyl)ethylamines and α-amino acids. The cytotoxicity of the synthesized pyrrolodiazepinones was studied. © 2018 American Chemical Society

A Straightforward Approach to Tetrahydroindolo[3,2-b]carbazoles and 1-Indolyltetrahydrocarbazoles through [3+3] Cyclodimerization of Indole-Derived Cyclopropanes

Dimerization is among the most challenging and fascinating reactions that, within one step, can provide a significant increase in structural complexity in a highly stereoselective manner. Indole-containing donor-acceptor cyclopropanes are appropriate candidates for dimerization reactions that provide rapid accesses to various biologically active bis-indole compounds. More information can be found in the Communication by E.M. Budynina, et al. (DOI: 10.1002/chem.201502287). © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Convenient approach to polyoxygenated dibenzo[: C, e] pyrrolo[1,2- a] azepines from donor-acceptor cyclopropanes

A short convenient approach to polyoxygenated tetrahydrodibenzo[c,e]pyrrolo[1,2-a]azepines from the donor-acceptor cyclopropanes was developed. A simple synthetic sequence involves: (a) cyclopropane ring opening with azide ion and Krapcho dealkoxycarbonylation; (b) azide-to-imine transformation followed by imine reduction; (c) the oxidative cyclization of 5-aryl-1-benzylpyrrolidin-2-ones, the key intermediates for this approach. © 2018 the Partner Organisations

Convenient approach to polyoxygenated dibenzo[: C, e] pyrrolo[1,2- a] azepines from donor-acceptor cyclopropanes

A short convenient approach to polyoxygenated tetrahydrodibenzo[c,e]pyrrolo[1,2-a]azepines from the donor-acceptor cyclopropanes was developed. A simple synthetic sequence involves: (a) cyclopropane ring opening with azide ion and Krapcho dealkoxycarbonylation; (b) azide-to-imine transformation followed by imine reduction; (c) the oxidative cyclization of 5-aryl-1-benzylpyrrolidin-2-ones, the key intermediates for this approach. © 2018 the Partner Organisations