A TCA-based Ideological and Political Teaching Model for the Biochemistry Course: Its Construction and Application / 中国生物化学与分子生物学报

Driven by initiatives of constructing the Four New Disciplines (new engineering, new medical sciences, new agriculture and new liberal arts) for higher education, Biochemistry teaching with ideological and political concerns is critical to the education achievements. Over the past 6 years, FMMU has carried out trials and practices on TCA model in Biochemistry teaching which can serve as a shared formula. TCA is originally an abbreviation for “tricarboxylic acid” cycle, and herein it stands for thinking and teamwork (T), critique (C) and appreciation (A), which hopefully could provide students with moral norms for cognition, science and life. Accordingly, a strategy is proposed to help systematically implement this “TCA” model, which highlights the notion of “3-integration for teaching”, “3-thinking for learning” and 3-step for setting”. Such “TCA”-based ideological and political model is adaptable to various universities in designing advanced teaching activities. In the case of FMMU, we created a “TCA pigeon” ideological and political pattern, with “pigeon” signifying medicine, the Air Force and peace, showing the distinctive features of a military medical university. Meanwhile, we have designed three advanced teaching activities. Specifically, “the magic biochemical-circle”, a shared learning platform that develops thinking abilities with a focus on autonomous learning and personal demonstration; “inter-guidance by basic and clinical teachers”, a heuristic large class that elicits critical thinking on basis of feedback, discussion and iteration; a task-driven “virtual reality (VR) program” enables students to deal with complicated situation and to undertake troubleshooting. The above “TCA pigeon” pattern has shown a generally favorable result among students in developing their skills such as holistic thinking, deep learning, introspecting and self-improvement. Yet, a few problems still occurred in practice and remained to be resolved.

Synthesis of Dipeptide, Amide, and Ester without Racemization by Oxalyl Chloride and Catalytic Triphenylphosphine Oxide.

An efficient triphenylphosphine oxide-catalyzed amidation and esterification for the rapid synthesis of a series of dipeptides, amides, and esters is described. This reaction is applicable to challenging couplings of hindered carboxylic acids with weakly nucleophilic amines or alcohols, giving the products in good yields (67-90%) without racemization. This system employs the highly reactive intermediate Ph3PCl2 as the activator of the carboxylate in a catalytic manner and drives the reaction to completion in a short reaction time (less than 10 min).

A One-Pot Ring-Opening/Ring-Closure Sequence for the Synthesis of Polycyclic Spirooxindoles.

One-pot ring-opening/ring-closure process of combining methyleneindolinone with 3-aminooxindole has been developed in this work. Novel polycyclic spirooxindoles were efficiently assembled under mild conditions in high yields (up to 95 %) with moderate to good diastereoselectivities (up to >95:5 d.r.) through simple filtration.

Organocatalytic, Enantioselective, Polarity-Matched Ring-Reorganization Domino Sequence Based on the 3-Oxindole Scaffold.

A one-pot squaramide-catalyzed enantioselective ring-reorganization domino sequence (Michael addition/intramolecular ring-opening/lactamization) of 3-hydroxyoxindole and methyleneindolinone, which can be readily derived from 3-oxindole, has been established in this work. As a result, novel polycyclic quinolinone-spirooxindoles bearing three contiguous chiral centers were efficiently and step-economically assembled under mild conditions in high yields (up to 97%) with excellent enantioselectivities (up to >99% ee) and moderate to good diastereoselectivities (up to >95:5 dr).

Photocatalytic reductive radical-radical coupling of N,N'-cyclicazomethine imines with difluorobromo derivatives.

A visible-light-induced difluoroalkylation of N,N'-cyclicazomethine imine was successfully realized through a novel photoredox radical-radical cross-coupling reaction. This developed protocol exhibits high functional group tolerance and affords a variety of difluorinated 3-pyrazolidinone scaffolds. Extensive mechanistic investigations have been undertaken, well revealing the involvement of a reductive radical-radical coupling pathway.

L-Pyroglutamic Sulphonamide as Hydrogen-Bonding Organocatalyst: Enantioselective Diels-Alder Cyclization to Construct Carbazolespirooxindoles.

Hydrogen-bonding organocatalysts L-pyroglutamic sulphonamides were readily synthesized for the first time by fully exploiting the potentials of L-pyroglutamic acid. The newly designed catalyst was successfully applied in catalyzing asymmetric Diels-Alder cyclization of methyleneindolinones with 2-vinyl-1H-indoles to efficiently assemble carbazolespirooxindoles in excellent stereoselectivity (up to 99% ee, >20:1 dr) and yields (up to 99%). Mechanistic studies disclosed that the well-designed hydrogen-bonding modes between L-pyroglutamic sulphonamide and substrates were crucial for stereocontrol in the cyclization.

Synthesis of pyrrolo(spiro-[2.3']-oxindole)-spiro-[4.3"]-oxindole via 1,3-dipolar cycloaddition of azomethine ylides with 3-acetonylideneoxindole.

A series of novel dispirooxindole derivatives, 3-acetyl-5-phenyl-pyrrolo(spiro-[2.3']-1'-benzyl-oxindole)-spiro-[4.3"]-1"-benzyl-oxindoles, were synthesized via 1,3-dipolar cycloaddition of the azomethine ylide with 3-acetonylideneoxindole in high regioselectivities and yields. An unusual regioselectivity was observed in this 1,3-dipolar cycloaddition, leading to the construction of novel dispirooxindole skeleton. The substituent effects on the regioselectivity were also investigated.