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This paper examines the economic asymmetries between a regret-averse firm and a risk-averse firm under price uncertainty. We show that the global and marginal effects of price uncertainty on production are both positive (negative) when regret aversion prevails if the random output price is asymmetrically distributed with positive (negative) skewness. In this case, high (low) output prices are much more likely to be seen than low (high) output prices. To minimize regret, the firm is induced to raise (lower) its output optimal level. The skewness of the price distribution as such plays a pivotal role in determining the regret-averse firm’s production decision price uncertainty.

We analyze a bank's risk taking in a two-moment decision framework. Our approach offers desirable properties like simplicity, intuitive interpretation, and empirical applicability. The bank's optimal behavior to a change in the standard deviation or the expected value of the risky asset's or portfolio's return can be described in terms of risk aversion elasticities, i.e., the sensitivity of the marginal rate of substitution between risk and return. The bank's investment in a risky asset position goes down when the return risk increases, if and only if the risk aversion elasticity exceeds − 1.

This paper examines the risk taking behavior of a banking firm facing ambiguity and possessing smooth ambiguity preferences. Ambiguity is modeled by a second-order probability distribution that captures the bank’s uncertainty about which of the subjective beliefs govern the return on its loans. Ambiguity aversion is modeled by a concave transformation of the (first-order) expected utility of profit conditional on each plausible subjective distribution of the random loan return. Within this framework, we show that the bank finds it less attractive to take risk in the presence than in the absence of ambiguity. This result extends to the case of greater ambiguity aversion. Given that the bank’s smooth ambiguity preferences exhibit non-increasing absolute ambiguity aversion, imposing a more stringent capital requirement to the bank has the desired effect that limits the bank’s incentive to take on excessive risk.

This paper examines the behavior of the competitive firm under price uncertainty. The firm has access to a futures market for hedging purposes. Basis risk exists because the random spot and futures prices are not identical at the time when the futures contracts mature. We show that the firm optimally produces less in the presence than in the absence of the basis risk. Furthermore, we demonstrate that the concept of expectation dependence that describes how the basis risk is correlated with either the random spot price or the random futures price plays a pivotal role in determining the firm’s optimal futures position. Specifically, an under-hedge is optimal if either the random spot price or the random futures price is negatively expectation dependent on the basis risk. On the other hand, an over-hedge is optimal if the random futures price is positively expectation dependent on the basis risk. The firm’s optimal futures position becomes indeterminate if the random spot price is positively expectation dependent on the basis risk.

This paper examines the behavior of the regret-averse firm under exchange rate uncertainty. Regret-averse preferences are characterized by a modified utility function that includes disutility from having chosen ex-post suboptimal alternatives. We show that the conventional results that the firm optimally produces less, sells more domestically, and export less abroad under uncertainty than under certainty holds if the firm is not too regret-averse. Using a binary model wherein the random spot exchange rate can take on either a low value or a high value with positive probability, we show that the conventional results may not hold, particularly when the firm is sufficiently regret-averse and the low spot exchange rate is very likely to prevail.

This note studies the risk-management decisions of a risk-averse farmer. The farmer faces multiple sources of price uncertainty. He sells commodities to two markets at two prices, but only one of these markets has a futures market. We show that the farmer's optimal commodity futures market position, i.e., a cross-hedge strategy, is actually an over-hedge, a full-hedge, or an under-hedge strategy, depending on whether the two prices are strongly positively correlated, uncorrelated, or negatively correlated, respectively.

We examine optimal production and export decisions of a firm facing exchange rate uncertainty, where the firm’s management is not only risk averse but also regret averse, i.e., is characterized by a utility function that includes disutility from having chosen ex post suboptimal alternatives. Experimental and empirical results support the view that managers tend to be regret averse. Under regret aversion a negative risk premium need not preclude the firm from exporting which would be the case if the firm were only risk averse. Exporting creates an implicit hedge against the possibility of regret when the realized spot exchange rate turns out to be high. The regret-averse firm as such has a greater ex ante incentive to export than the purely risk averse firm. Finally, we use a two-state example to illustrate that the firm optimally exports more (less) to the foreign country than in the case of pure risk aversion if the low (high) spot exchange rate is more likely to prevail. Regret aversion as such plays a crucial role in determining the firm’s optimal allocation between domestic sales and foreign exports.

This paper revisits the impact of regret aversion on the behavior of the competitive firm under price uncertainty. We show that the firm optimally produces more (less) when regret aversion prevails if the random output price is positively (negatively) skewed. In this case, high (low) output prices are much more likely to be seen than low (high) output prices. To avoid regret, the firm is induced to raise (lower) its output optimal level. The skewness of the price distribution as such plays a pivotal role in determining how regret aversion affects the firm’s production decision.

The synthesis and properties of boron-rich bis(meta-carbaborane) derivatives containing glycophosphonate and glycophosphonothioate moieties are reported. All compounds are water-soluble; however, the tetragalactosylated compounds show lower solubility than their disodium salts.

A facile synthesis of carbaboranediyl-bis(glycophosphonates) and corresponding phosphonothioates is presented. These compounds show extraordinarily high water solubility and low cytotoxicity. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

Novel bis-phosphonate derivatives of carbaboranes, which might be potential boron-delivery agents for boron neutron capture therapy, are described. Conceivable synthetic routes which failed to give the desired compounds are discussed, and finally, a highly selective route to the target molecules is reported.

The industrial organization approach to the microeconomics of banking augmented by uncertainty and risk aversion is used to examine credit derivatives and macro derivatives as instruments to hedge credit risk for a large commercial bank. In a partial{analytic framework we distinguish between the probability of default and the loss given default, model difierent forms of derivatives, and derive hedge rules and strong and weak separation properties between deposit and loan decisions on the one hand and hedging decisions on the other. We also suggest how bank{speciflc macro derivatives could be designed from common macro indices which serve as underlyings of recently introduced flnancial products.

Routes allowing the synthesis of moenomycin analogues with one modified sugar component and with new lipid parts were developed (see 10c, 12c, 16b, and 20b in Schemes 2–4). It is anticipated that such analogues will be useful for studying the mode of action of the moenomycin-type transglycosylase inhibitors in detail and for preparing analogues with improved pharmacokinetic properties.

A new approach for the synthesis of moenomycin trisaccharide analogues is reported in which three monosaccharide building blocks are used and allows the introduction of different substituents at the 6-position of unit E (Scheme 2). Furthermore, a new procedure for the introduction and manipulation of unit F is described (Scheme 3).

Oxidation of 4,6-heptadienoic acid systems with hydrogen peroxide in the presence of a catalytic amount of diphenyl diselenide leads to 5-(3-hydroxypropenyl)dihydrofuran-2-one systems with defined relative configuration at the 4 and 7 positions (carboxylic acid numbering). A system having a six-membered ring as part of the s-trans-diene system was an intermediate in a strigol total synthesis; a second system lacking the six-membered ring is the subject of the present publication. We accomplished a stereoselective synthesis of the diene system by (i) trapping a π-allyl palladium complex with lithium diphenylphosphinite to give an allylic diphenylphosphane oxide and (ii) a subsequent Horner−Wittig reaction. The species that brings about the oxidative 1,4-addition is benzeneperoxyseleninic acid. We also report observations that shed some light on the mechanism. (© Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002)

The synthesis of some 3-aryl-3-(trifluoromethyl)3H-diazirine and benzophenone-based photoaffinity labels is reported. The photolabile group is bound to a scaffold that also accommodates functional groups to which an indicator unit (biotin) and the bioactive ligand can be attached orthogonally. To three of the labels, moenomycin was conjugated with the aim to provide tools for the identification of the moenomycin binding site within the transglycosylase domain of the enzyme PBP 1b. Some preliminary photoaffinity-labeling experiments were carried out.

Upon feeding of [2-(13)C,4-(2)H]-1-deoxy-D-xylulose to Streptomyces ghanaensis, the deuterium label was retained exclusively at positions C-7 and C-17 in the moenocinol part of the moenomycin antibiotics. This result vindicates the hypothesis that the C(25) structure of moenocinol is assembled from a C(10) and a C(15) precursor, each of which requires for its formation the involvement of a dimethylallyl diphosphate starter unit.

1α-Amino-1,6,9-trideoxy forskolin was synthesized starting from drimenal and an isoprenoid C5 unit. A tricyclic labdane with the entire forskolin skeleton was available in only four steps. Barton's nitrite photolysis was applied to functionalize C-1.

Conditions allowing optically active methyl glycerate to be converted, without racemization, into the 2-O-propargyl derivative, via the 2-O-allyl derivative, are reported. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)

The interaction of a moenomycin derivative with the enzyme penicillin binding protein 1b (PBP 1b) has been studied by means of STD NMR. The results obtained initiated the synthesis of a number of moenomycin derivatives modified in unit A including a moenomycin-ampicillin conjugate and determination of their antibiotic activities. A protocol is described that allows studying the interaction of moenomycin analogues with PBP 1b by fluorescence correlation spectroscopy.

We use a model of a bank under perfect competition to examine effects of derivatives for tradeable and non tradeable risks on optimal bank behavior in the deposit and loan markets. If both credit risk and interest risk are tradeable, we identify simple decision rules which require only market and cost data for setting deposit and loan volumes optimally. In the case of non tradeable risks, however, optimal behavior also depends on the degree of risk aversion, the distributions of random variables and the financial resources of the bank. Simple decision rules then no longer exist.

An approach for the synthesis of moenomycin A12 C-glycoside partial structures is reported.

The moenomycins A and C 1 as well as penta-, di- and monosaccharide analogues have been conjugated to BSA and biotin, respectively. The moenomycin A–BSA conjugates have been used to raise polyclonal antibodies. It has been demonstrated that the antisera recognize moenomycin A.

The antibiotic moenomycin A inhibits the biosynthesis of peptidoglycan, the main structural polymer of the bacterial cell wall. The inhibition is based on a reversible binding of the antibiotic to one of the substrate binding sites at enzymes such as the penicillin binding protein 1b (PBP 1b). This binding has been employed to isolate PBP 1b by affinity chromatography. Suitable ligands have been prepared from moenomycin A and coupled both to affinity supports and to surface plasmon resonance sensor surfaces. The reactions that take place upon immobilization of the ligands to the affinity support and the sensor surface, respectively, have been studied in detail. With the help of surface plasmon resonance the optimal conditions for binding of PBP 1b to moenomycin-derivated ligands have been established. For the first time the selective binding of the moenomycin sugar moiety to the enzyme has been demonstrated.

Moenomycin has been highly selectively converted into amino derivative 3b. The primary amino group of this compound can be used to attach various fluorescent labels to moenomycin, through conversion of isothiocyanates into thioureas and squaric acid diesters into diamides. The application of some of the derivatives is outlined. (© Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002)

p-Alkoxy-substituted cinnamylthiouronium salts 7, 13, 21a, and 21b reacted selectively with the 2-acylamino-1,3-cyclopentanedione unit A of moenomycin A (1) to give the corresponding 2-alkylated products 14a, 14b, 22a, and 22b. These products, depending on the pH of the solution, were either stable under the reaction conditions or they underwent retro-Claisen-type reactions. The method can be used for the attachment of reporter groups to moenomycin A for the synthesis of, for example, 25. (© Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002)

An approach for the synthesis of moenomycin A12 C-glycoside partial structures is reported based on allyltin chemistry.

Conditions are reported which allow to convert optically active methyl glycerate to the 2- O -allyl derivative without racemization. Cross metathesis reactions then lead to analogues of the 2- O -alkyl glycerate part of the moenomycin antibiotics.

Nuclease-resistant moenomycin-binding aptamers with dissociation constants in the range of 300 to 400 nM have been selected. Competition experiments have demonstrated that these aptamers recognize a disaccharide analogue of moenomycin. The results offer the opportunity of setting up a selective and sensitive assay for identifying moenomycin biosynthetic precursors.

From a moenomycin A glycolic aldehyde degradation product lacking the chromophore unit and most of the lipid part, a number of amines were prepared by reductive amination. Their interaction with artificial membranes as well as their transglycosylase inhibiting and antibiotic properties were studied.

From moenomycin A both the chromophore part and the lipid side chain were degraded by ozonolysis to give an analogue with a glycolaldehyde unit in 2-position of the glyceric acid moiety. The aldehyde was converted to a number of homoallylic alcohols by indium-mediated Barbier-type reactions with allylic and benzylic halides. With exception of the phytyl bromide-derived reaction product all compounds were antibiotically inactive.

Polythiophene films containing ester groups on the surface of electrodes are interesting potential carrier materials for reagents. Methyl thiophene-3-acetate (3) can be copolymerized with 3-methylthiophene (1) and 3-butylthiophene (2) by means of cyclic voltammetry (CV) at potentials of 0–2.2 V. Higher potentials (0–2.4 V) lead to overoxidation of the copolymers. The ester groups were confirmed by FTIR spectra. Electrochemical investigations of 2,2′-bithiophene (6) and 3 at equimolar ratios showed no successful copolymerization at potentials of 0–1.3 V. If the copolymerization experiments of 6 with 1 or 3 were carried out at molar ratios of 1:50 at 1.3 V, 6 with its low oxidation potential was polymerized without copolymerization of the other monomers. However, if the oxidation potential was increased stepwise from 1.3 V, the oxidation of 1 or 3 occurred, forming copolymers containing both monomer components. HPLC investigations of solutions containing mixtures of 6 and 3 and also 6 and 1 in acetonitrile/TEABF4 showed, after exhaustive oxidation at a potential of 1.3 V, the complete absence of 6; 1 and the ester 3 were not oxidized and copolymerized at these potentials. From the results of the copolymerization experiments, as well as the HPLC investigations, it can be concluded that the dominant mechanism of the electrochemical polymerization is radical cation dimerization.

A benzoylbenzoyloxy derivative of digitoxigenin has been prepared which is the first cardenolide with an affinity label in the lactone ring. It inhibits the Na+/K+-ATPase almost as effectively as digitoxigenin itself. The activity was lost when in addition a biotin tag was attached to ring A.

Feeding experiments ( 13C and 15N-labeled precursors) shed light on the biosynthetic origin of the chromophore (unit A of 1), the N-acetyl groups, the 4-C-methyl group of the moenuronamide unit (part F of 1), the sugar units, and the lipid part (unit I of 1) of the antibiotic moenomycin A(1). The lipid part is completely isoprenoid and is constructed via the non-mevalonate pathway. The central C 10 part originates from a precursor like geranyl or linalyl diphosphate and is formed by a route involving ring formation between C-2 and C-6 of the monoterpene unit, two successive rearrangements to give a 7-membered ring intermediate and cleavage of the ring between C-5 and C-11 (moenocinol numbering).

A photolabel, a biotin tag, and a moenomycin ligand have been attached orthogonally to the three functional groups of isoserine to provide compound 13 that is to be used in affinity labeling of penicillin binding protein 1b . The urethane group in 13 can be cleaved with n -butylamine in methanol or water.

The lipid part of the moenomycins is completely isoprenoid and is constructed via the non-mevalonate pathway. The central C 10 part originates from a precursor like geranyl or linalyl diphosphate and is formed by a route involving ring formation between C-2 and C-6 of the monoterpene unit, two successive rearrangements to give a seven-membered ring intermediate and cleavage of the ring at the C-5 and C-11 bond (moenocinol numbering).

The synthesis of two iodoformates is described. 3α-Iodo-5α-cholestane-2β-yl formate (6) reacts under the usual Woodward–Prevost conditions to provide the expected hydroxyformates 5 and 7. Unfortunately, a 6β-formyloxy-7α-iodo-labdane derivative, prepared in the context of forskolin synthetic studies, could not be forced to react analogously.