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Objective Prior studies suggest knowledge of estimated fetal weight (EFW), particularly by ultrasound (US), increases the risk for cesarean delivery. These same studies suggest that concern for macrosomia potentially alters labor management leading to increased rates of cesarean delivery. We aimed to assess if shortened labor management, as a result of suspected macrosomia (≥4,000 g), leads to an increased rate of cesarean delivery. Study Design This is a secondary analysis of a retrospective cohort study at a single tertiary center in 2015 of women with singleton pregnancies ≥36 weeks with documented EFW by US within 3 weeks or physical exam on admission. Women were excluded if an initial cervical exam was ≥6 cm or no attempt was made to labor. In addition, patients were excluded for the diagnosis of hypertension, diabetes, or prior cesarean delivery, as these comorbidities influence the use of US, labor management, and cesarean delivery independent of fetal weight. Patients were classified as EFW of ≥4,000 and Results Of 1,506 patients included, 54 (3.5%) had EFW of ≥4,000 g. Women with EFW of ≥4,000 g had a larger body mass index, higher fetal birth weight, were more likely to be undergoing induction of labor, had a more advanced gestational age, and were more likely to have had an US within 3 weeks of delivery. They were more likely to undergo cesarean delivery (29.6 vs. 9.3%, adjusted odds ratio [AOR]: 2.7, 95% confidence interval [CI]: 1.3–5.5) despite not having shortened labor times. When analyzing this population by method of obtaining EFW, those with EFW based on US rather than external palpation were more likely to undergo cesarean delivery (13.1 vs. 7.9%, AOR: 1.5, 95% CI: 1.01–2.12), again without having shortened labor times. Conclusion EFW of ≥4,000 g and use of US to estimate fetal weight do not appear to shorten labor management despite being associated with an increased risk of cesarean delivery.

A Povarov reaction, between an aromatic imine derived from cinnamaldehyde and a cyclic enamide, was employed to rapidly construct the tricyclic core of the alkaloids martinelline and martinellic acid. The cycloaddition was completely regioselective though the exo/endo selectivity was poor. The diastereoisomers were readily separated by flash chromatography and the relative stereochemistry of the exo-isomer confirmed by single crystal X-ray crystallography. This intermediate was converted to the central core of the aforementioned alkaloids in five additional synthetic operations.

Terminally N-substituted dienes derived from 3-methylisoindolin-1-one, 4-isopropyl- and 4-phenyloxazolidin-2-one undergo Diels–Alder reaction with a range of activated dienophiles. The reactions reported are completely regio- and endo-selective, with the diastereoisomeric excess with respect to the auxiliary good to excellent in most of the cases reported. A model has been developed for rationalising the stereochemical outcome of these reactions.

Formal [4+2] cycloaddition of cyclic enamides with imines derived from aromatic amines gave the 4-arylhexahydropyrroloquinoline skeleton in one step as mixtures of diastereoisomers. Aromatic imines derived from formaldehyde and methylglyoxalate also participated in this chemistry, with the latter favouring formation of the endo -cycloadduct. The cycloadducts derived from methylglyoxalate were unstable and fragmented to give highly substituted quinolines under both neutral and basic conditions. Imines derived from 3-cyanoacrolein also underwent cycloaddition and gave an advanced potential precursor to martinellic acid, albeit with poor diastereoselectivity.

Piclavines A1 and A2 have been synthesised for the first time. The route is short with the key step being the reaction of a bicyclic N -acyl iminium ion with 3-trimethysilyl-1-decene. This convergent strategy gave exclusively compounds in which the pendant decenyl group was axial , as a 6:1 mixture of E : Z- alkene diastereoisomers. Reduction of the lactam carbonyl group gave a 6:1 mixture of piclavines A1 and A2.

Treatment of the bicyclic iminium ion derived from 5-methoxyhexahydroindolizidin-3-one with allyltrimethylsilane gave exclusively the diastereoisomer in which the allyl group was axial. This substrate is a useful precursor to 5-propyl-3-alkylindolizidine alkaloids.

The tricyclic core of martinelline and martinellic acid was rapidly assembled utilising an imino Diels–Alder reaction of an imine derived from cinnamaldehyde with a cyclic enamide. The cycloaddition was completely regioselective though the exo – endo selectivity was poor. These diastereoisomers were readily separated by flash chromatography and the relative stereochemistry of the exo -isomer confirmed by single crystal X-ray crystallography. This intermediate was converted to the central core of the aforementioned alkaloids in five additional synthetic operations.

Formal [4+2] cycloaddition of cyclic enamides with imines derived from aromatic amines gave the 4-arylhexahydropyrroloquinoline skeleton in one step as mixtures of diastereoisomers. Aromatic imines derived from formaldehyde and methylglyoxalate also participated in this chemistry, with the latter favouring formation of the endo -cycloadduct. The cycloadducts derived from methylglyoxalate were unstable and fragmented to give highly substituted quinolines under both neutral and basic conditions. Imines derived from 3-cyanoacrolein also underwent cycloaddition and gave an advanced potential precursor to martinellic acid, albeit with poor diastereoselectivity.

The tricyclic core of martinelline and martinellic acid was rapidly assembled utilising an imino Diels–Alder reaction of an imine derived from cinnamaldehyde with a cyclic enamide. The cycloaddition was completely regioselective though the exo – endo selectivity was poor. These diastereoisomers were readily separated by flash chromatography and the relative stereochemistry of the exo -isomer confirmed by single crystal X-ray crystallography. This intermediate was converted to the central core of the aforementioned alkaloids in five additional synthetic operations.

Terminally N-substituted dienes derived from 3-methylisoindolin-1-one, 4-isopropyl- and 4-phenyloxazolidin-2-one undergo Diels–Alder reaction with a range of activated dienophiles. The reactions reported are completely regio- and endo-selective, with the diastereoisomeric excess with respect to the auxiliary good to excellent in most of the cases reported. A model has been developed for rationalising the stereochemical outcome of these reactions.

Piclavines A1 and A2 have been synthesised for the first time. The route is short with the key step being the reaction of a bicyclic N -acyl iminium ion with 3-trimethysilyl-1-decene. This convergent strategy gave exclusively compounds in which the pendant decenyl group was axial , as a 6:1 mixture of E : Z- alkene diastereoisomers. Reduction of the lactam carbonyl group gave a 6:1 mixture of piclavines A1 and A2.

A novel class of calixarene derivatives with phosphine oxide residues [Calix-(OCH2CH2POPh2)n] attached to the lower rim showing high efficiency in extraction of EuIII, ThIV, PuIV, and AmIV from simulated nuclear waste is reported.

The rate constant ( k t ) for electron transfer between a donor radicalanion and an acceptor can be determined by electrochemical methods when the so-formed acceptor radicaanion undergoes irreversible fragmentation. When fast bond clevage (rate constant, k r ) occurs within the encounter pair for electron transfer the experimental relationship between log k t and E ° D does not give sufficient information to define the parameters for electron transfer and bond cleavage of the acceptor molecule. The value of E ° A becomes uncertain within a small range. knowledge of k r removes this uncertainty in E ° A .

A range of oxaziridines bearing an α-hydrogen atom on the N-alkyl substituent react with tertiary amines at ambient temperature to yield N-unsubstituted aldimines.

Reaction of 2′-bromodeoxybenzoins with copper powder in refluxing dimethylacetamide gives the corresponding 2-phenylfuran in good yields.

Certain 1-alkyl-2,4,6-trisubstituted pyridinium salts form π-radicals by electrochemical reduction which are stable in dimethylformamide on the scale of cyclic voltammetry, whereas the corresponding 1-benzyl and 1-allyl compounds undergo carbon–nitrogen bond cleavage at measured rates which are dependent on the size of the 2,6-substituents.

A variety of cycloheptatrienyl-phosphorus derivatives have been prepared. In no case was evidence obtained of contribution from norcaradiene forms. Attempts to prepare the corresponding ylide from cycloheptatrienyltriphenylphosphonium salts led to substitution of phosphine, as did reactions with a variety of nucleophiles, including hydroxide ion where the observed reaction is in conflict with earlier reports.

Reaction of 2′-bromodeoxybenzoins with copper powder in refluxing dimethylacetamide gives the corresponding 2-phenylfuran in good yields.

A range of oxaziridines containing N-methylene substituents has been synthesized by peracid oxidation of the corresponding fluorenylidene N-alkylamines. Spontaneous and tertiary amine base-catalysed decomposition of the oxaziridines into unstable NH aldimines and derivatives was observed. Acrylaldehyde, 2-methylacrylaldehyde, and benzaldehyde NH imines have been identified as initial products from decomposition of the corresponding oxaziridines. 2,4,6-Trialkylhexahydro-1,3,5-triazines, N,N′-dialkylidene-1,1 -diaminoalkanes, N,N′-diarylidene-1,1 -diaminoalkanes, and N-iso-butylidene-2-methylpropenylamine were among the isolated products formed via the undetected alkyl aldehyde NH imines resulting from oxaziridine decomposition.