NO donors are routinely used as the exogenous source in in vitro studies. However, the kinetics or the dose of NO release from the existing donors is not readily monitored. This complicates the elucidation of the involvement of NO in a biological response. We report herein a series of NO donors (NOD545a-g), whose NO release is triggered by UV light at 365 nm or a two-photon laser at 740 nm, and importantly, their NO release is accompanied by a drastic fluorescence turn-on, which has been harnessed to follow the kinetics and dose of NO release in a real-time fashion with spectroscopic methods or microscopic methods in in vitro studies. These merits have rendered NOD545a-g useful molecular tools in NO biology.

Classic fluorescent dyes, such as coumarin, naphthalimide, fluorescein, BODIPY, rhodamine, and cyanines, are cornerstones of various spectroscopic and microscopic methods, which hold a prominent position in biological studies. We recently found that 9-amino-benzo[c]cinnoliniums make up a novel group of fluorophores that can be used in biological studies. They are featured with a succinct conjugative push-pull backbone, a broad absorption band, and a large Stokes shift. They are potentially useful as a small-molecule alternative to R-phycoerythrin to pair with fluorescein in multiplexing applications.

An iodine-promoted one-pot cascade oxidative annulation reaction has been developed for the synthesis of chromone-fused-pyrrolo­[2,1-a]­isoquinolines and indolizino­[8,7-b]­indoles from o-acetylphenoxyacrylates, tetrahydroisoquinolines, and noreleagnines. This process underwent a logical approach to both chromone-fused-pyrrolo­[2,1-a]­isoquinolines and chromone-fused-indolizino­[8,7-b]­indoles isolamellarin derivatives. Manipulations of l-menthol and dl-α-tocopherol demonstrate the applications of this strategy.

Dedication to Prof. Weisheng Tian on the occasion of his 70th birthdayOrganoboron compounds are versatile synthons in synthetic chemistry, materials science, and medicinal chemistry. The preparation of them often requires either reactive organometallic reagents or transition metals. In recent years, transition-metal-free borylation methodologies using radical chemistry for CÀ B bond formation have attracted much attention and developed rapidly, which circumvents the use of preformed organometallic reagents. Various successful ap-proaches from different radical precursors (such as carboxylic acids, amines and alcohols, which are abundant in nature) through either thermochemical, photochemical or electrochemical pathways have been developed. Therefore, in this review, we hope to provide an overview of recent advances in the discovery, development, and mechanistic study of transitionmetal-free radical borylation processes. Borylation of CÀ N BondsAmines are cheap, widely commercially available, and are abundant in drugs and natural products. Thus, transforming readily available amines and amine derivatives into valuable boronic esters will be of great use.

An iodine‐promoted one‐pot cascade oxidative annulation reaction has been developed for the synthesis of [1,2,3]triazolo[1,5‐a]quinolines from methyl azaarenes and N‐tosylhydrazines. The reaction has a broad substrate scope and can be easily scaled up to gram‐scale. 1,2,3‐Triazoles are an important skeletal structure for the construction of C−C and C−P bonds, 2‐cyclopropylquinolines and imidazo[1,5‐a]quinolines, for which different synthetic applications were explored.

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An oxidative [3+1+1] convergent domino cyclization is disclosed. This protocol enables to get quinoline, quinoxaline, quinazolin‐4(3H)‐one and benzo[d]thiazole attached 2,4,5‐trisubstituted oxazoles from methyl azaarenes, benzoins, and NH4OAc in the presence of iodine and molecular sieves without any metal catalyst. The reaction features wide substrate scope, good functional group tolerance, mild reaction conditions, and easily available substrates.