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Comprehensive Summary: The difunctionalization of bicyclo[1.1.0]butanes is an under‐explored transformation that accesses to moieties that are otherwise difficult to prepare. Herein, a new oxidative radical alkylarylation of N‐aryl bicyclobutyl amides with C(sp3)−H feedstocks is achieved in an atom‐economic and photocatalyst‐ and light‐free manner. This protocol follows a sequential C(sp3)–H/C(sp2)–H functionalization, providing an efficient route for diversity‐oriented synthesis of functionalized 3‐spirocyclobutyl oxindoles. In particular, a wide range of C(sp3)−H feedstocks, including ether, alcohol, amine, thioether, polychlorinated methane, silane, acetone, acetonitrile, toluene, and alkane are all suitable for the C(sp3)−H functionalization, demonstrating the broad applicability of this transformation. [ABSTRACT FROM AUTHOR]

A new radical relay approach for the efficient construction of alkylsulfonated indolo[2,1-a]isoquinoline-6(5H)-ones in moderate to good yields under mild conditions via SO2 insertion/Smiles rearrangement/intramolecular cyclization is developed. This approach utilizes 4-alkyl substituted Hantzsch esters as alkyl radical sources and further undergoes in situ SO2 insertion to obtain alkylsulfonyl radical species, which avoids the use of unstable alkyl sulfonyl chlorides and highly toxic sulfonyl hydrazides. Additionally, this method for the direct assembly of alkylsulfonated polycyclic molecule skeletons displays high chemical selectivity, broad substrate scope, and step-economy. [ABSTRACT FROM AUTHOR]

A direct visible‐light‐promoted radical‐triggered tandem cyclization of 1,7‐diene systems with cyclic sulfonium salts by using copper(I)‐based complexes as photoredox catalyst is developed. With this approach, a variety of sulfur‐containing polycyclic derivatives are prepared through alkylation/6‐exo‐trig cyclization/5‐exo‐trig cyclization of 1,7‐diene systems under mild conditions. In addition, the photoinduced copper‐catalyzed ring‐opening of cyclic sulfonium salts provides the alkyl radical intermediates, which prefers addition to the C−C double bond that connected to the aromatic ring rather than the electron‐deficient vinyl in 1,7‐dienes. Moreover, oxidation of the desired sulfur‐containing polycyclic products provides a strategy for the preparation of remote nitrogen‐fused polycyclic substituted sulfoxide or sulfone‐containing derivatives. [ABSTRACT FROM AUTHOR]

An immobilized lipase with metal‐organic frameworks (MOFs) was first used for the kinetic resolution of mandelic acid enantiomers by transesterification reaction using vinyl acetate as acyl donor in organic medium. Notably, the biocompatibility of the carrier and catalytic performance of lipase could be significantly improved via modification of NH2‐Ni‐MOF with polyvinylpyrrolidone. After extensively screening the enzymatic process, the optimal enantioselective resolution conditions and excellent outcomes were obtained for the enzyme‐catalyzed transesterification reaction. In addition, the recovered immobilized lipase displayed outstanding reusability after immobilization. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: The asymmetric total synthesis of an unusual C25 steroid containing a unique bicyclo[4.4.1]undecene A/B ring system, resulting in the synthesis of cyclocitrinol (1) and its isomer Δ8,14‐cyclocitrinol (38), is reported. Initial attempts to construct the synthetically challenging bicyclo[4.4.1]undecene A/B ring system using a type II [5+2] cycloaddition showed that a chiral substituent at the allylic position of the alkene (C6, cyclocitrinol numbering) controlled the stereoselective outcome of the cycloaddition reaction. Late‐stage migration of the tetrasubstituted C8–C14 double bond in Δ8,14‐cyclocitrinol (38) to obtain cyclocitrinol (1) proved challenging, inspiring an alternative approach. The chiral β‐CH2OR group on the allylic substituent at C6 played a pivotal role both in controlling the diastereoselectivity of the type II [5+2] cycloaddition and retaining the C6 substituent under lithium–amine conditions. [ABSTRACT FROM AUTHOR]

Background: A phase II study was performed to investigate the safety and efficacy of weekly doses of combined paclitaxel and 5-fluorouracil (5-FU) with concurrent radiation therapy, followed by 2 cycles of consolidation chemotherapy to treat patients with advanced oesophageal carcinoma.Methods: The eligibility criteria included local, advanced, newly diagnosed and postoperative local regional lymph node metastasis; an Eastern Cooperative Oncology Group (ECOG) score of ≤ 2; and adequate organ function. Patients received chemoradiotherapy consisting of radiotherapy (50.4 Gy/28 Fx or 61.2 Gy/34 Fx) and concurrent paclitaxel (50 mg/m2) and 5-FU (300 mg/m2) for 96 h on days 1, 8, 15, 22, and 29. The two-cycle consolidation chemotherapy protocol included paclitaxel (175 mg/m2) plus continuously infused 5-FU (1800 mg/m2) for 72 h administered on days 57 and 85, after concurrent chemoradiotherapy.Results: Between February 2012 and August 2013, 53 patients with oesophageal carcinoma were enrolled in the study. Among these patients, 33 (62.2%) were newly diagnosed and 20 (37.7%) had postoperative local regional lymph node metastasis. The median overall survival (OS) time was 17.9 months (95% CIs = 11.9-23.9), and the median progression-free survival (PFS) time was 12.4 months (95% CIs = 8.6-16.1). Approximately 84.9% (45/53) and 50.9% (27/53) of the patients completed ≥ 5 cycles and all 7 cycles of chemotherapy, respectively. Approximately 86.7% (46/53) of patients completed radiation therapy. The 1-, 2-, and 3-year OS rates were 66.0%, 37.7%, and 35.8%, respectively. The 1-, 2-, and 3-year local control rates were 76.9%, 66.4%, and 66.4%, respectively. Seventeen patients (32%) experienced grade 3 or higher toxicity. Grade 3 to 5 toxicity during chemoradiotherapy included neutropaenia (7.5%), thrombocytopaenia (1.8%), fatigue (7.5%), anaemia (1.8%), dermatitis radiation (1.8%), pneumonitis (5.6%), oesophagitis (9.4%) and vomiting (3.7%).Conclusions: The combination of weekly doses of paclitaxel and 5-FU was well tolerated and produced comparable results among patients with locally advanced oesophageal cancer. A randomised phase III trial (NCT01591135) comparing paclitaxel plus 5-FU with cisplatin plus 5-FU is on-going at our hospital. [ABSTRACT FROM AUTHOR]

A new metal-free oxidative radical [2+2+1] carbocyclization of benzene-linked 1, n-enynes with two C(sp3)H bonds adjacent to the same heteroatom is described. This method achieves two C(sp3)H oxidative functionalizations and an annulation, thus providing efficient and general access to a variety of fused five-membered carbocyclic hydrocarbons. [ABSTRACT FROM AUTHOR]

Difunktionalisierung: Preiswertes und umweltschonendes FeCl3 katalysiert die oxidative 1,2 ‐ Alkylarylierung aktivierter Alkene zu Verbindungen mit einer Aryl ‐ C(sp2) ‐ H ‐ und einer C(sp3) ‐ H ‐ Bindung in Nachbarschaft zu einem Heteroatom. Die Reaktion nutzt DBU als Liganden und TBHP als Oxidationsmittel und bietet eine neue Strategie für die Synthese von Oxindolen (siehe Schema, TBHP=tert ‐ Butylhydroperoxid). [ABSTRACT FROM AUTHOR]

We here describe a new copper-catalyzed oxidative coupling of acids with alkanes for the selective synthesis of allylic esters and alkylalkenes. This method achieves multiple dehydrogenation and esterification, representing a new unactivated C(sp3)–H oxidative esterification of acids with common alkanes. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: The asymmetric total synthesis of an unusual C25 steroid containing a unique bicyclo[4.4.1]undecene A/B ring system, resulting in the synthesis of cyclocitrinol (1) and its isomer Δ8,14‐cyclocitrinol (38), is reported. Initial attempts to construct the synthetically challenging bicyclo[4.4.1]undecene A/B ring system using a type II [5+2] cycloaddition showed that a chiral substituent at the allylic position of the alkene (C6, cyclocitrinol numbering) controlled the stereoselective outcome of the cycloaddition reaction. Late‐stage migration of the tetrasubstituted C8–C14 double bond in Δ8,14‐cyclocitrinol (38) to obtain cyclocitrinol (1) proved challenging, inspiring an alternative approach. The chiral β‐CH2OR group on the allylic substituent at C6 played a pivotal role both in controlling the diastereoselectivity of the type II [5+2] cycloaddition and retaining the C6 substituent under lithium–amine conditions. [ABSTRACT FROM AUTHOR]

A new palladium-catalyzed oxidative difunctionalization reaction of N-arylalkenes with primary, secondary, and tertiary α-carbonyl alkyl bromides affording indolinones is presented. The reaction is initiated by a Heck insertion and requires the addition of Ag2CO3. This transformation includes tandem C--Br/C--H functionalization and cyclization steps that occur through an oxidative radical pathway. [ABSTRACT FROM AUTHOR]

The title reaction leads to fused five-membered carbocyclic hydrocarbons. [ABSTRACT FROM AUTHOR]