Capital substitutability and weak sustainability revisited: The conditions for capital substitution in the presence of risk

The capital approach is frequently used to model sustainability. A development is deemed to be sustainable when capital is not reduced. There are different definitions of sustainability, based on whether or not they allow that different forms of capital may be substituted for each other. A development that allows for the substitution of different forms of capital is called weakly sustainable. This article shows that in a risky world and a risk-averse society even under the assumptions of weak sustainability the circumstances under which different forms of capital may be substituted are limited. This is due to the risk-reducing effect of diversification. Using Modern Portfolio Theory this article shows under which conditions substitution of different forms of capital increases risk for future generations.

The relationship between counterfactual thinking and emotional reactions to event outcomes: Does one account fit all?

By enabling a comparison between what is and what might have been, counterfactual thoughts amplify our emotional responses to bad outcomes. Well-known demonstrations such as the action effect (the tendency to attribute most regret to a character whose actions brought about a bad outcome) and the temporal order effect (the tendency to undo the last in a series of events leading up to a bad outcome) are often explained in this way. An important difference between these effects is that outcomes are due to decisions in the action effect, whereas in the temporal order effect outcomes are achieved by chance. In Experiment 1, we showed that imposing time pressure leads to a significant reduction in the action but not in the temporal order effect. In Experiment 2, we found that asking participants to evaluate the protagonists (

Multi component coupling reactions of N-acetyl-2-azetine

N-Acetyl-2-azetine undergoes Lewis acid catalysed formal [4+2]-cycloaddition with imines derived from aromatic amines to initially give an approximately 1: 1 mixture of exo-endo-diastereoisomeric 1-(2a,3,4,8b-tetrahydro-2H-1,4-diaza-cyclobuta[a]naphthalen-1-yl)-ethanone cycloadducts which were detected by proton NMR spectroscopy. These products, which were too unstable to isolate, and characterise, reacted further with aromatic amines to give 2,3,4-trisubstituted tetrahydroquinolines in good to excellent yield, predominantly as a single diastereoisomer, with the minor diastereoisomer converting to the major diastereoisomer on silica. The cycloaddition was irreversible and a mechanism is presented for the formation of the major diastereoisomer from the mixture of diastereoisomeric intermediates. A range of conditions is described for converting the 2,3,4-trisubsitituted tetrahydroquinolines into 2,3-disubstituted quinolines.

Three component coupling reactions of N-acetyl-2-azetine-rapid stereoselective entry to 2,3,4-trisubstituted tetrahydroquinolines

N-Acetyl-2-azetine undergoes Lewis acid catalysed [4 + 2]-cycloaddition with imines derived from aromatic amines and gave a 1:1 mixture of exo-endo diastereoisomeric azetidine cycloadducts which reacted further with aromatic amine, to give 2,3,4-trisubsitituted tetrahydroquinolines in good to excellent yield, predominantly as one diastereoisomer.

Hylambatin and (Thr)11-hylambatin from the skin secretion of the African hyperoliid frog, Kassina maculata: Structural characterisation, precursor cDNA cloning and preliminary pharmacological testing

The tachykinins hylambatin and (Thr)11-hylambatin have been isolated from the defensive skin secretion of the African hyperoliid frog, Kassina maculata,. Hylambatin (DPPDPNRFYGMMamide) is revised in structure from the original sequence by a single site substitution (Asn/Asp at position 6), and (Thr)11-hylambatin, a novel tachykinin, differs in structure from hylambatin by a single Thr/Met substitution. (Thr)11-hylambatin is five- to ten-fold more abundant than hylambatin in secretions. Synthetic replicates of both peptides were active in smooth muscle preparations including the rat tail artery, rat ileum and bovine trachea. While hylambatin displayed activity consistent with an NK1-receptor ligand, (Thr)11-hylambatin was more active than either substance P or neurokinin A in both NK1- and NK-2 receptor rich preparations. Incorporation of a threoninyl residue rather than the canonical leucyl residue at the penultimate position in both substance P and neurokinin A, generated active ligands in both arterial and intestinal smooth muscle preparations. Hylambatin precursor cDNAs, designated HYBN-1 and HYBN-2, respectively, were cloned from a skin library by 3'- and 5'-RACE reactions. Both were highly-homologous containing open-reading frames of 66 amino acids encoding single copies of either hylambatin or (Thr)11-hylambatin. These data reveal a hitherto unrecognized structure/activity attribute of mammalian tachykinin receptors revealed though discovery of a novel amphibian skin-derived, site-substituted peptide ligand.

A study of Heck cyclization reactions to form phenanthridine ring systems

A survey of conditions for the palladium catalyzed intramol. Heck cyclization of protected amines has shown that the Herrmann-Beller palladacycle can be exploited under 'cationic' conditions to provide a robust and rapid route (

Transamidation reactions of  -lactams: a synthesis of ( )-dihydroperiphylline.

Ammonolysis of N-(halogenoalkyl)azetidin-2-ones affords medium ring azalactams via transamidation but large or strained rings are not isolated, acyclic ?-amino-amides being produced; two successive transamidative ring expansions from 4-phenylazetidin-2-one give a synthesis of (?)-dihydroperiphylline (I).

N-H insertion reactions of rhodium carbenoids. Part 2. Preparation of N-substituted amino(phosphoryl)acetates (N-substituted phosphorylglycine esters).

Rhodium(II) acetate-catalyzed reaction of Et 2-diazo-2-diethoxyphosphorylate, EtO2CC(:N2)PO(OEt)2, with carbamates, amides, ureas or anilines gives a range of N-substituted 2-amino-2-diethoxyphosphorylacetates, EtO2CCH(NHR1)PO(OEt)2 (where R1 = Boc, Cbz, acetyl, propionyl, pivaloyl, n-Pr, Ph and substituted Ph groups), by N-H insertion reaction of the intermediate rhodium carbenoid.

N-H insertion reactions of rhodium carbenoids. Part 1. Preparation of  -amino acid and  -aminophosphonic acid derivatives.

Rh(II) acetate-catalyzed decompn. of diazophenylacetates PhC(N2)CO2Me 1 and PhC(N2)CO2R* 3 [R*OH = (-)-borneol, (+)-menthol, (-)-8-phenylmenthol] in the presence of a range of N-H compds. results in an N-H insertion reaction of the intermediate carbenoids and formation of N-substituted phenylglycine derivs. PhCH(NR1R2)CO2Me 2 [R1 = R2 = Et; R1 = 4-MeOC6H4, COCH2CHMe2, CO2CH2Ph, (S)-CH(CO2Me)CH2Ph, (S)-CHMePh, R2 = H; 64-83% yields] and PhCH(NR1R2)CO2R* 4 (R1 = R2 = Et; R1 = COMe, CO2Me, R2 = H; same R*; 37-71% yields). The corresponding reactions of di-Me ?-diazobenzylphosphonate PhC(N2)P(O)(OMe)2 5 with primary amines constitute a simple route to aminophosphonates PhCH(NHR)P(O)(OMe)2 6 (R = COMe, COEt, CO2CH2Ph, CO2CMe3, 4-ClC6H4, 4-MeC6H4, 4-MeOC6H4; 13-96% yields).