Developing Food Products For Consumers on a Gluten Free Diet

There is a significant increase in people that choose to follow an avoidance diet, especially excluding gluten. Unlike previously, there is now a demand for ‘no compromise’ gluten-free cereal products that have the same properties as their wheat contain counterparts. This is very challenging for the bakers and the cereal technologists due to the functional role of the gluten network in some of these products. Numerous combinations of raw materials form natural sources have been studied and critically evaluated in this review. Most of the gluten-free products are made of native and modified starches blended with different hydrocolloids due to their structure-building and water binding properties. These ingredients are added to a gluten-free flour, such as rice and corn. The legislation framework, formulations for manufacturing of highl nutritional value bread, pasta and cakes/biscuits as well as quality assurance aspects for the gluten-free manufacturers are discussed in this review.

Natural substances and high pressure processing to preserve sea bass

Esta tese teve como objectivo estudar estratégias de conservação de pescado fresco, recorrendo ao uso de extractos e óleos essenciais de plantas e do processamento por alta pressão (HPP), usando filetes de robalo como um caso de estudo modelo. Relativamente aos extractos e óleos essenciais, avaliaram-se as suas propriedades antibacterianas e antioxidantes. Os extractos aquosos quente de poejo e de orégão e o óleo essencial de cravinho apresentaram a maior actividade antioxidante. Os óleos essenciais foram mais eficientes do que os extractos para inibir o crescimento das estirpes bacterianas testadas, tendo-se observado os menores valores de concentração mínima inibitória nos óleos essenciais de orégão, citronela, alho e orégão Espanhol. De seguida, estudou-se o efeito dos óleos essenciais de orégão Espanhol e de limão na conservação de filetes de robalo fresco tendo em conta critérios microbiológicos, químicos, físicos e sensoriais. A aplicação do óleo essencial de orégão Espanhol aumentou o tempo de vida útil dos filetes sob o ponto de vista bacteriano, mas não em termos sensoriais. A combinação dos óleos essenciais de orégão Espanhol e de limão melhorou o efeito antioxidante e reduziu a intensidade do odor e a sua eficácia em relação às Enterobacteriaceae, comparando com o tratamento com óleo essencial de orégão Espanhol per se. No sentido de reduzir o odor conferido pelos óleos essenciais realizou-se um estudo de conservação para avaliar o efeito de películas com óleos essenciais (citronela, alho e tomilho) em filetes de robalo, recorrendo a uma teste de desafio bacteriano. As películas sem óleos essenciais aumentaram o tempo de vida útil sob o ponto de vista bacteriano, mas este efeito não foi observado com a incorporação dos óleos essenciais nas películas. Em relação ao HPP, testaram-se diversas condições (nível de pressão, tempo de pressurização e taxa de pressurização) e avaliaram-se os efeitos na actividade enzimática, na qualidade global e na conservação de filetes de robalo fresco. Em geral, o aumento do nível de pressão e do tempo de pressurização diminuiu a actividade da fosfatase ácida e das enzimas proteolíticas, a carga bacteriana e a capacidade de retenção de água, enquanto que os filetes ficaram mais brancos. O HPP revelou potencial para o desenvolvimento de novos produtos: mais brancos, não translúcidos, mais firmes e com maior tempo de frescura e estabilidade microbiológica. Em conclusão, os óleos essenciais e o HPP têm potencial para conservar pescado fresco, devido aos seus efeitos na qualidade bacteriana. Ainda assim, mais esforços devem ser feitos no sentido de reduzir a transferência de odor dos óleos essenciais para o pescado e os efeitos do HPP no aspecto do pescado e na oxidação lipídica.

Extraction of added-value products from biomass using ionic liquids

The main purpose of this thesis is to investigate the potential of ionic liquids (ILs) as a new class of extractive solvents for added-value products from biomass. These include phenolic compounds (vanillin, gallic, syringic and vanillic acids), alkaloids (caffeine) and aminoacids (L-tryptophan). The interest on these natural compounds relies on the wide variety of relevant properties shown by those families and further application in the food, cosmetic and pharmaceutical industries. Aiming at developping more benign and effective extraction/purification techniques than those used, a comprehensive study was conducted using aqueous biphasic systems (ABS) composed of ILs and inorganic/organic salts. In addition, ILs were characterized by a polarity scale, using solvatochromic probes, aiming at providing prior indications on the ILs affinity for particular added-value products. Solid-liquid (S-L) extractions from biomass and using aqueous solution of ILs were also investigated. In particular, and applying and experimental factorial design to optimize the operational conditions, caffeine was extracted from guaraná seeds and spent coffee. With both types of extractions it was found that it is possible to recover the high-value compounds and to recycle the IL and salt solutions. Finally, aiming at exploring the recovery of added-value compounds from biomass using a simpler and more suistainable technique, the solubility of gallic acid, vanillin and caffeine was studied in aqueous solutions of several ILs and common salts. With the gathered results it was possible to demonstrate that ILs act as hydrotropes and that water can be used as an adequate antisolvent. This thesis describes the use of ILs towards the development of more effective and sustainable processes.

Light harvesting in solar cells using natural pigments from red fruits adsorbed to mesoporous TiO2

Nature has developed strategies to present us with a wide variety of colours, from the green of leaves to the bright colours seen in flowers. Anthocyanins are between these natural pigments that are responsible for the great diversity of colours seen in flowers and fruits. Anthocyanins have been used to sensitize titanium dioxide (TiO2) in Dye-Sensitized Solar Cells (DSSCs). DSSCs have become one of the most popular research topic in photovoltaic cells due to their low production costs when compared to other alternatives. DSSCs are inspired in what happens in nature during photosynthesis. A primary charge separation is achieved by means of a photoexcited dye capable of performing the electron injection into the conduction band of a wide band-gap semiconductor, usually TiO2. With this work we aimed to synthesize a novel mesoporous TiO2 structure as the semiconductor in order to increase the dye loading. We used natural occurring dyes such as anthocyanins and their synthetic flavylium relatives, as an alternative to the widely used metal complexes of Ru(II) which are expensive and are environmentally unsafe. This offers not only the chance to use safer dyes for DSSCs, but also to take profit of waste biological products, such as wine and olive oil production residues that are heavily loaded with anthocyanin dyes. We also performed a photodegradation study using TiO2 as the catalyst to degrade dye contaminants, such as those from the wine production waste, by photo-irradiation of the system in the visible region of the light spectrum. We were able to succeed in the synthesis of mesoporous TiO2 both powder and thin film, with a high capacity to load a large amount of dye. We proved the concept of photodegradation using TiO2 as catalyst. And finally, we show that wine production waste is a possible dye source to DSSCs application.

Synthesis of ring A of (+)-Ambruticin S and bicyclic nucleosides for antisense drug technology

La synthèse énantiosélective de la (+)-ambruticine S, un produit naturel antifongique a été effectuée au sein de notre groupe. Trois approches ont été développées pour la synthèse du fragment lactone (cycle A). Ces trois voies d’accès au cycle A ont pour intermédiaire commun le methyl α-D-glycopyranoside déjà porteur du diol requis et disponible commercialement à bon prix. Une désoxygénation de l’hydroxyle en C-4 et l’homologation d’un carbone de la chaine latérale en C-6 ont permis l’obtention du cycle lactonique A. Le deuxième projet est une collaboration entre le groupe Hanessian et ISIS Pharmaceuticals afin de développer de nouveaux oligonucléosides antisens. Les nucléosides antisens [4.3.0]-bicycliques cis et trans ont été synthétisés avec succès à partir d’un monosaccharide naturel commun, L-arabinose, porteur des stéréocentres requis. Un réaction clé d’allylation de Sakurai a permis d’obtenir les diastéréoisomères cis et trans dans des conditions de contrôle de type Felkin-Ahn et de contrôle par chélation respectivement. Les composés bicycliques finaux cibles ont été obtenus par une réaction d’aldol intramoléculaire catalyzéé par la proline, par métathèse de fermeture de cycle et par l’application de la méthode de Vorbrüggen pour la synthèse de nucléosides.

Synthèse d’un inhibiteur de la rénine, l’aliskiren et développement de méthodes catalytiques d’alkylation asymétrique

Une nouvelle approche pour la synthèse de l’aliskiren, un puissant inhibiteur de la rénine pour le traitement de l’hypertension chez l’homme, a été développée. De cette approche, des étapes clés tels qu’une allylation avec un des catalyseurs de MacMillan, une cyclisation par métathèse (RCM) pour la préparation d’une lactone à neuf membres et une séquence de réactions d’aziridination diastéréosélective/réarrangement de cycle par une catalyse acide donnant un produit aminohydroxylé ont permis de compléter la synthèse de l’aliskiren en 11 étapes. Durant l’élaboration de la séquence de réactions pour la préparation de l’aliksiren, il a été noté que la lactone à neuf membres avait une facilité à se réarranger via des intermédiaires quinonoïdaux et les produits issus de cette tendance ont été analysés. De plus, une étude sur la réaction de RCM, donnant la lactone à neuf membres, a montré une dépendance envers la nature diastéréomérique du substrat de départ. Une méthodologie d’alpha-allylation asymétrique de cétones catalysée au palladium, tirant avantage d’un ligand chiral PHOX, a été explorée et utilisée en vue de la synthèse de l’aliskiren. De cette méthode, une étude pour la synthèse de produits alpha-allylcétones acycliques a été démontrée et un effet d’additif sur la sélectivité et la vitesse de réaction a été découvert. De plus, la production d’un intermédiaire avancé d’un produit d’intérêts a été accomplie et la nature de la contribution de l’additif a été investiguée. Les produits obtenus depuis la méthodologie d’allylation catalysée au palladium et la formation d’intermédiaire cationique des certains dérivés de la synthèse de l’aliskiren ont inspirés une nouvelle approche faisant appel à des techniques d’alkylation en catalyse acide pour la formation de produits diaryliques. Il a été trouvé que le catalyseur de chlorure d’or(III) et de triflate de bismuth(III) étaient particulièrement efficaces, démontrant une différence de cinétique pour la réactivité d’un mélange diastéréoisomériques d’alcools alpha-substitués de départ.

Progrès vers la synthèse totale de l'hodgsonox

Ce mémoire présente une poursuite de l’étude vers la synthèse de l’hodgsonox, un sesquiterpénoïde naturel possédant des propriétés insecticides contre la mouche verte d’Australie, Lucilia cuprina. L’hodgsonox comporte six centres stéréogènes et trois cycles : un époxyde fusionné à un cycle à cinq chaînons et une fonction éther cyclique à six chaînons doublement allylique. La stratégie de synthèse de l’hodgsonox proposée comporte dix-neuf étapes linéaires. Elle s’appuie sur les travaux préliminaires de Lise Bréthous, étudiante au doctorat, de Nicolas Lévaray, étudiant à la maîtrise, ainsi que du Dr. Ying Dong Lu et de la Dr. Sonia Diab, qui ont tous travaillé précédemment dans le groupe de la Pr. Lebel. La première étape de cette synthèse consiste en une hydrogénation cinétique dynamique de Noyori permettant d’obtenir un seul diastéréoisomère à partir de l’α-acétylbutyrolactone. Une séquence de six étapes linéaires supplémentaires, comprenant l’ouverture de la lactone ainsi qu’une métathèse d’oléfine, permet d’obtenir le cycle à cinq chaînons avec un rendement global de 37%. L’unité isopropyle est par la suite installée par une addition conjuguée pour former un éther d’énol silylé, qui est directement oxydé en la cétone correspondante avec l’acétate de palladium(II). Une réaction d’hydrosilylation subséquente permet d’obtenir la stéréochimie syn attendue de l’unité isopropyle. Par la suite, la carbonylation d’un intermédiaire triflate permet d’obtenir le squelette de base pour la formation de l’éther cyclique. Enfin, le cycle à six chaînons est formé par insertion O−H intramoléculaire d’un diazo avec un rendement global de 2% sur 17 étapes. Les travaux spécifiques de l’auteure comprennent l’évaluation de conditions catalytiques pour l’oxydation de Saegusa de l’éther d’énol silylé. Les trois dernières étapes ont également été explorées par l’auteure. Il s’agit de l’époxydation de la double liaison endocyclique, de l’insertion dans un lien O−H catalysée par un dimère de rhodium, et de la méthylénation. Enfin, l’exploration d’une voie alternative a été entamée. Cette nouvelle voie consiste à former l’éther cyclique par une substitution nucléophile sur un époxyde. La double liaison exo-cyclique serait installée par une simple réaction de déshydratation.

Model Compound Studies on the Devulcanization of Natural Rubber Using 2, 3-Dimethyl-2-Butene

The mechanism of devulcanization of sulfur-vulcanized natural rubber with aromatic disulfides and aliphatic amines has been studied using 23-dimethyl-2-butene (C5H1,) as a low-molecular weight model compound. First C6H12 was vulcanized with a mixture of sulfur, zinc stearate and N-cyclohexyl-2-benzothiazylsulfenamide (CBS) as accelerator at 140 °C, resulting in a mixture of addition products (C(,H 1 i-S,-C5H 1 i ). The compounds were isolated and identified by High Performance Liquid Chromatography (HPLC) with respect to their various sulfur ranks. In it second stage, the vulcanized products were devulcanized using the agents mentioned above at 200 °C. The kinetics and chemistry of the breakdown of the sulfur-hridges were monitored. Both devulcanization agents decompose sulfidic vulcanization products with sulfur ranks equal or higher than 3 quite effectively and with comparable speed. Di phenyldisulfide as devulcanization agent gives rise to a high amount of mono- and disulfidic compounds formed during the devulcanization, hexadecylamine, as devulcanization agent, prevents these lower sulfur ranks from being formed.

The utilisation of latex reclaim rubber in natural rubber

Scrap latex products contain rubber hydrocarbon of very high quality, that is only slightly crosslinked. A novel economic technique for converting such latex waste into a processible material is developed. This paper reports the effect of adding this latex reclaim to natural rubber. It is shown that latex reclaim can replace raw natural rubber up to about 50 wt.% without affecting mechanical properties.

Studies on the Bioactive Natural Antioxidants From Oilseeds

Antioxidants are substances that when present at low concentrations compared to that of an oxidisable substrate significantly delays or inhibits oxidation of that substrate in food products or in living systems. Antioxidants are either endogenous to the body or derived from the diet. Several types of synthetic antioxidants like BHT, BHA, TBHQ etc. are also used in the food industry. However, findings and subsequent publicity has fostered significant consumer resistance to the use of synthetic food additives as antioxidants, colourants etc. and therefore food industry is in search of potential natural antioxidants from edible sources.The major dietary sources of antioxidant phytochemicals are cereals, legumes, fruits, vegetables, oilseeds, beverages, spices and herbs. In the present study, we have focused on rice bran and its byproducts. Rice is one of the oldest of food crops and has been a staple food in India from very ancient times. It is also the staple food for about 60% of the world's population. Rice bran is a byproduct of the rice milling industry and is a potential commercial source of a healthy edible oil viz. rice bran oil and a variety of bio-active phytochemicals.Defatted rice bran (DRB), a byproduct of rice bran oil extraction, is also a good source of insoluble dietary fiber, protein, phytic acid, inosito I, vitamin B and a variety of other phytochemicals. Though the antioxidant potential of DRB has been demonstrated, it still remained a relatively unexplored source material, which demanded further investigation especially with regard to its detailed phytochemical profile leading to practical application. The focus of the present investigation therefore has been on DRB primarily to establish its phytochemical status and feasibility of using it as a source of bio-active phytochemicals and natural antioxidants leading to value addition of DRB otherwise used as cattle feed. To gain a better understanding of the value of rice bran as a source of phytochemicals, five popular rice varieties of the region viz. PTB 50, PTB 39, PTB 38, JA Y A, and MO 10 and a wild variety (oryza nivara) that is mainly used for medicinal applications in traditional ayurvedic system were characterized along with commercial samples of rice bran. The present study also explains the feasibility of a process for the extraction, enrichment, and isolation of antioxidant compounds from DRB. The antioxidant potential of the extracts were evaluated both in bulk oils and in food relevant model emulsions, using standard in vitro models. Radical scavenging effects, indicative of possible biological effects, were also evaluated.

Utilization of rice by-products in rubber

The thesis consists of seven chapters. The first chapter is a general introduction on rice by-products, their composition and utilization at present. The different milling processes adopted in paddy and the major by-products obtained from these processes viz. rice husk, rice bran, rice bran oil and rice husk ash are described. The physical properties and chemical composition of the rice husk and its general uses are given in detail. The chemical composition of the rice bran and its separation from paddy is also included. The details of solvent extraction process used for obtaining rice bran oil and also its chemical constitution is discussed in this chapter. Also described is the preparation and the different uses of rice husk ash. A literature survey is also done on the utilization of rice by-products in rubber and plastics as on today. The scope and objectives of the present study is also included at the end of this chapter.

Studies On Vulcanization, Rheology And Reinforcement Of Natural Rubber Latex With Special Reference To Accelerator Combinations, Surface Active Agents And Gamma Irradiation

In the present work, studies on vulcanization, rheology and reinforcement of natural rubber latex with special reference to accelerator combinations, surface active agents and gamma irradiation have been undertaken. In vulcanization, the choice of vulcanization system, the extent and mc-zie of vulcanization and network structure of the vulcanizate are important factors contributing to the overall quality of the product. The vulcanization system may be conventional type using elemental sulfur or a system involving sulfur donors. The latter type is used mainly in the manufacture of heat resistant products. For improving the technical properties of the products such as modulus and tensile strength, different accelerator combinations are used. It is known that accelerators have a strong effect on the physical properties of rubber vulcanizates. A perusal of the literature indicates that fundamental studies on the above aspects of latex technology are very limited. Thereforea systematic study on vulcanization, rheology and reinforcement of natural rubber latex with reference to the effect of accelerator combinations, surface active agents and gamma irradiation has been undertaken. The preparation and evaluation of some products like latex thread was also undertaken as a part of the study. The thesis consists of six chapter

Radiopacity and Chemical resistance of Elastomer-Barium sulphate nanocomposites with special reference to Natural Rubber, Ethylene Propylene Rubber and Isobutylene Isoprene Rubber

The Human race of our century is in gluttonous search for novel engineering products which led to a skyrocketed progress in research and fabrication of filled polymers. Recently, a big window has been opened up for speciality polymers especially elastomers with promising properties. Among the many reasons why rubbers are widely used in the process industries, three are considered as important. Firstly, rubbers operate in a variety of environments and possess usable ranges of deformity and durability and can be exploited through suitable and more or less conventional equipment design principles. Secondly, rubber is an eminently suitable construction material for protection against corrosion in the chemical plant and equipment against various corrosive chemicals as, acids and alkalies and if property tailored, can shield ionising radiations as X-rays and gamma rays in medical industry, with minimum maintenance lower down time, negligible corrosion and a preferred choice for aggressive corroding and ionising environment. Thirdly, rubber can readily and hastily, and at a relatively lower cost, be converted into serviceable products, having intricate shapes and dimensions. In a century’s gap, large employment of flexible polymer materials in the different segments of industry has stimulated the development of new materials with special properties, which paved its way to the synthesis of various nanoscale materials. At nano scale, one makes an entry into a world where multidisciplinary sciences meet and utilises the previously unapproached infinitesimal length scale, having dimension which measure upto one billionth of a meter, to create novel properties. The nano fillers augment the elastomers properties in an astonishing fashion due to their multifunctional nature and unprecedented properties have been exhibited by these polymer-nanocomposites just to beat the shortcomings of traditional micro composites. The current research aims to investigate the possibility of using synthesised nano barium sulphate for fabricating elastomer-based nanocomposites and thereby imparting several properties to the rubber. In this thesis, nano materials, their synthesis, structure, properties and applications are studied. The properties of barium sulphate like chemical resistance and radiopacity have been utilized in the present study and is imparted to the elastomers by preparing composites

A Modeling Analysis of Changing Global Land Use as affected by Changing Demands for Wood Products

The 21st century has brought new challenges for forest management at a time when globalization in world trade is increasing and global climate change is becoming increasingly apparent. In addition to various goods and services like food, feed, timber or biofuels being provided to humans, forest ecosystems are a large store of terrestrial carbon and account for a major part of the carbon exchange between the atmosphere and the land surface. Depending on the stage of the ecosystems and/or management regimes, forests can be either sinks, or sources of carbon. At the global scale, rapid economic development and a growing world population have raised much concern over the use of natural resources, especially forest resources. The challenging question is how can the global demands for forest commodities be satisfied in an increasingly globalised economy, and where could they potentially be produced? For this purpose, wood demand estimates need to be integrated in a framework, which is able to adequately handle the competition for land between major land-use options such as residential land or agricultural land. This thesis is organised in accordance with the requirements to integrate the simulation of forest changes based on wood extraction in an existing framework for global land-use modelling called LandSHIFT. Accordingly, the following neuralgic points for research have been identified: (1) a review of existing global-scale economic forest sector models (2) simulation of global wood production under selected scenarios (3) simulation of global vegetation carbon yields and (4) the implementation of a land-use allocation procedure to simulate the impact of wood extraction on forest land-cover. Modelling the spatial dynamics of forests on the global scale requires two important inputs: (1) simulated long-term wood demand data to determine future roundwood harvests in each country and (2) the changes in the spatial distribution of woody biomass stocks to determine how much of the resource is available to satisfy the simulated wood demands. First, three global timber market models are reviewed and compared in order to select a suitable economic model to generate wood demand scenario data for the forest sector in LandSHIFT. The comparison indicates that the ‘Global Forest Products Model’ (GFPM) is most suitable for obtaining projections on future roundwood harvests for further study with the LandSHIFT forest sector. Accordingly, the GFPM is adapted and applied to simulate wood demands for the global forestry sector conditional on selected scenarios from the Millennium Ecosystem Assessment and the Global Environmental Outlook until 2050. Secondly, the Lund-Potsdam-Jena (LPJ) dynamic global vegetation model is utilized to simulate the change in potential vegetation carbon stocks for the forested locations in LandSHIFT. The LPJ data is used in collaboration with spatially explicit forest inventory data on aboveground biomass to allocate the demands for raw forest products and identify locations of deforestation. Using the previous results as an input, a methodology to simulate the spatial dynamics of forests based on wood extraction is developed within the LandSHIFT framework. The land-use allocation procedure specified in the module translates the country level demands for forest products into woody biomass requirements for forest areas, and allocates these on a five arc minute grid. In a first version, the model assumes only actual conditions through the entire study period and does not explicitly address forest age structure. Although the module is in a very preliminary stage of development, it already captures the effects of important drivers of land-use change like cropland and urban expansion. As a first plausibility test, the module performance is tested under three forest management scenarios. The module succeeds in responding to changing inputs in an expected and consistent manner. The entire methodology is applied in an exemplary scenario analysis for India. A couple of future research priorities need to be addressed, particularly the incorporation of plantation establishments; issue of age structure dynamics; as well as the implementation of a new technology change factor in the GFPM which can allow the specification of substituting raw wood products (especially fuelwood) by other non-wood products.

Zur Herstellung von chiralen α-Aminosäuren mit α-quartären Zentren und deren Verwendung als Synthone in der organischen Synthese

Ziel dieser Arbeit war, ausgehend von alpha-Aminoaldehyden eine kurze und effiziente Synthese zur Darstellung von Aminosäuren mit alpha-quartären Zentren in enantiomerenreiner Form und davon ableitbare wichtige Synthone in der organischen Synthese zu entwickeln. Der enantiomerenreine 2-tert-Butyl-4-methyl-1,3-oxazolidin-4-carbaldehyd ist via kupfer-katalysierter Aziridinierung des enantiomerenangereicherten 2-tert-Butyl-5-methyl-4H-1,3-dioxins mit der Nitrenquelle (N-Tosylimino)phenyliodinan zugänglich. Eine anschließende Oxidation mit Natriumhyperchlorid und Wasserstoffperoxid führt zur korrespondierenden Carbonsäure, die via sauer katalysierter Acetalspaltung und nachfolgender Abspaltung der Tosyl-Schutzgruppe in enantiomerenreines alpha-Methylserin in sehr guten Ausbeuten umgewandelt werden kann. Mit dem Einsatz von in C5-Position Ethyl-substituiertem 2-tert-Butyl-4H-1,3-dioxin ist analog das N-Tosyl geschützte alpha-Ethylserin darstellbar. Um die bestehende Lösungsmittelabhängigkeit in weniger polaren Losungsmitteln wie Dichlormethan oder Diethylether der Aziridinierung in Bezug auf ihre Diastereoselektivität und Reaktivität zu minimieren, wurden unterschiedliche Nitrenquellen untersucht. [N-(p-Methoxybenzolsulfonyl)imino]methoxyphenyliodinan stellte sich als die potenteste Nitrenquelle heraus und die Ausbeute konnte auf bis zu 70% gesteigert werden. Die Anwendbarkeit des N-Tosyl geschützten alpha-Methylserins konnte mit der Synthese des β-Lactons und 2-Carboxylethylether-2-aziridin unter Mitsunobu-Bedingungen gezeigt werden. Dabei ist die Reaktion durch einfache Variation des Lösungsmittels und der Reaktionstemperatur zu beiden Produkten in sehr guten Ausbeuten hin steuerbar. Das β-Lacton konnte anschließend erfolgreich in das N-Tosyl- und S-Acetyl- geschützte alpha-Methylcystein überführt werden.