Christoph Garbers

Abstract Die C‐Methylbestimmungsmethode nach Kuhn‐Roth wird in der Weise abgeändert, dass die entstandene Essigsäure papierchromatographisch relativ bestimmt wird. Dadurch gelingt es, die C‐Methylbestimmungen mit 0,2–0,4 mg Substanz auszuführen.

Research Article| April 01 1960 The transport of vitamin A in rat serum with special reference to the occurrence of unidentified metabolites of vitamin A in the rat C. F. Garbers; C. F. Garbers 1Joint Nutrition Unit of the South African Council for Scientific and Industrial Research and the University of the Witwatersrand, Johannesburg Search for other works by this author on: This Site PubMed Google Scholar J. Gillman; J. Gillman 1Joint Nutrition Unit of the South African Council for Scientific and Industrial Research and the University of the Witwatersrand, Johannesburg Search for other works by this author on: This Site PubMed Google Scholar M. Peisach M. Peisach 2National Chemical Research Laboratory, South African Council for Scientific and Industrial Research, Pretoria, South Africa Search for other works by this author on: This Site PubMed Google Scholar Biochem J (1960) 75 (1): 124–132. https://doi.org/10.1042/bj0750124 Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Facebook Twitter LinkedIn Email Cite Icon Cite Get Permissions Citation C. F. Garbers, J. Gillman, M. Peisach; The transport of vitamin A in rat serum with special reference to the occurrence of unidentified metabolites of vitamin A in the rat. Biochem J 1 April 1960; 75 (1): 124–132. doi: https://doi.org/10.1042/bj0750124 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentAll JournalsBiochemical Journal Search Advanced Search This content is only available as a PDF. © 1960 CAMBRIDGE UNIVERSITY PRESS1960 Article PDF first page preview Close Modal You do not currently have access to this content.

Abstract Ausgehend von dem Tetraol II wurden durch Wasserabspaltung die drei Polyene IV, V und VI dargestellt, von denen das erstere zwei Acetylenverbindungen, die letzteren eine Acetylen‐ und eine kumulengruppe bzw. zwei Kumulengruppierungen enthalten. Die partielle Reduktion des Diecetylen‐Derivates führte zum Di‐cis‐(5,6; 13,14)‐1,18‐diphenyl‐3,7,12,16‐tetamethyl‐octadecanonaen VII; aus V und VI liessen sich bei der partiellen Reduktion anderecis‐Formen fassen.

Abstract Aus Benzalaceton, Propargylbromid und Magnesium wurde 1‐Phenyl‐3‐methyl‐hexen‐(1)‐in‐(5)‐ol‐(3) (III) hergestellt, welches durch Erhitzen mit wasserfreier Oxalsäure im Vakuum in 1‐Phenyl‐3‐methyl‐hexadien‐(1,3)‐on‐(5) (6‐Phenyl‐4‐methyl‐hexadien‐(3,5)‐on‐(2)) (IV) übergeht.

Abstract Aus 1,18 ‐Diphenyl‐3,7,12,16‐tetramethyl‐octadeca‐diin‐ (5,13)‐heptaen‐(1,3,7,9,11,15,17) (I) sowie aus 1,18‐Diphenyl‐3,7,12,16‐tetramethyl‐octadeca‐in‐ ( 5 ) ‐nonaen‐ (1,3,7,9,11,13,14,15,17) (II)konnten durch partielle Reduktion zwei kristallisierte, sehr ähnliche Pigmente isoliert werden, Von denen das eine das 1,18‐Diphenyl‐3,7,12,16 ‐ tetramethyl‐ octadeca‐2in‐(5)‐octaen‐(1,3,7,9,11,13,15,17)(IIIa), das andere das 1, 18‐Diphenyl‐3,7,12,16,‐tetramethyl‐octa‐deca‐decaen‐(1,3,4,5,7,9,11,13,15,17) (III) zu sein scheint. Die beiαden Pigmente III a und III lieferten bei der partiellen Reduktion mit Wasserstoff und Palladium das 5,6‐Mono‐cis‐l, 18‐diphenyl‐tetra‐methyl‐octadeca‐nonaen (IV), welches unter der Wirkung von Jod zum ganz‐trans‐l,18‐Diphenyl‐3,7,12,16‐tetramethyl‐octadecanonaen isomerisiert wird.

Abstract Aus dem Tetraol I, 2,6,10,14,19,23,27,31‐Octamethyl‐dotriaconta‐heptaen‐(2,6,8,16,24,26,30)‐ diin‐(12,20)‐tetraol‐(10,14,19,23), wurden durch Wasserabspaltung 3 ungesättigte Kohlenwasserstoffe, die Bis‐dehydro‐lycopine a, b und c erhalten, für welche die Formeln IIa, IIb und IIc in Frage kommen. Zwei dieser Verbindungen wurden durch partielle Reduktion in cis‐Lycopine (b, c, c′) übergeführt, welche, mindestens teilweise, cis‐Konfiguration an sog. „verbotenen”︁ Doppelbindungen besitzen. Alle dargestellten ungesättigten Kohlenwasserstoffe dieser Reihe erwiesen sich als relativ unbeständig.

Cis- and trans-ocimenones were identified as constituents of oil of Tagetes minuta L. and their structures verified by synthesis.

Abstract Aus einem Polyen‐diacetylen‐tetraol I wurde durch Abspaltung von Wasser ein „Bis‐dehydro‐β‐carotin”︁ oder eine Mischung von solchen Carotinen erhalten, aus dem sich durch partielle Reduktion zwei cis‐β‐Carotine mit cis‐Konfiguration an „behinderten”︁ Doppelbindungen herstellen liessen. Die beiden Substanzen, die mit cis‐β‐Carotin B und cis‐β‐Carotin C bezeichnet werden, sind stabile, schön kristallisierte Verbindungen, die durch Erhitzen oder durch Einwirkung von Jod in ganz‐trans‐β‐Carotin umgelagert werden. Die Spektren beider cis‐β‐Carotine zeigen die flachen Absorptionskurven, welche für cis‐Polyene mit cis‐Konfiguration an „behinderten”︁ Stellen charakteristisch sind.

The identification of four further major constituents of the pedal gland exudate of the bontebok, Damaliscus dorcas dorcas, viz. alpha-terpineol, 2-n-heptylpyridine, m-cresol and (A)-6-dodecen-4-olide and the investigation of the stereochemistry of the double bond in (Z)-6-dodecen-4-olide by means of iterative computer analysis are described. An improved synthesis of this compound is outlined.

Abstract γ‐Carotin wurde zum ersten Male totalsynthetisch hergestellt. Neben diesem Pigment bildete sich in grösserer Menge β‐Carotin.

An efficient and mild catalytic deallylation method of aryl allyl ethers is developed, with commercially available Ni(COD)2 as catalyst precursor, simple substituted bipyridine as ligand and air-stable hydrosilanes. The process is compatible with a variety of functional groups and the desired phenol products can be obtained with excellent yields and selectivity. Besides, by detection or isolation of key intermediates, mechanism studies confirm that the deallylation undergoes η3-allylnickel intermediate pathway.

Abstract The significance of pheromones in olfactory communication in mammals, and the possibility of using synthetic pheromones to influence the behaviour of problem animals, are briefly discussed. The isolation, identification and synthesis of the principal volatile component contained in the pedal gland exudate of the bontebok, Damaliscus dorcas dorcas, viz. (Z)-5-undecen-2-one, are reported. Some of the other major constituents of the secretion have been identified as 2-heptanone, 2 -nonanone, 2 -undecanone and 2,5-undecanedione.

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cis-2 Vitamin A acid and the hitherto unknown cis-2,cis-4 vitamin A acid are obtained by condensation of 3-methyl-5-(1,3,3-trimethylcyclohexenyl)penta-trans-2,trans-4-dienylidenephosphorane (IV) with cis-β-formyl-crotonic acid (II). Controlled stereomutation of the cis-2,cis-4-acid yielded cis-2- and all-trans vitamin A acid. cis-β-Formylcrotonic acid is isomerised to the trans-acid (I) by treatment with base.

Helvetica Chimica ActaVolume 38, Issue 6 p. 1490-1490 Article Zur Kenntnis des Vitamins B12 C. F. Garbers, C. F. Garbers Zürich, Chemisches Institut der UniversitätSearch for more papers by this authorH. Schmid, H. Schmid Zürich, Chemisches Institut der UniversitätSearch for more papers by this authorP. Karrer, P. Karrer Zürich, Chemisches Institut der UniversitätSearch for more papers by this author C. F. Garbers, C. F. Garbers Zürich, Chemisches Institut der UniversitätSearch for more papers by this authorH. Schmid, H. Schmid Zürich, Chemisches Institut der UniversitätSearch for more papers by this authorP. Karrer, P. Karrer Zürich, Chemisches Institut der UniversitätSearch for more papers by this author First published: 1955 https://doi.org/10.1002/hlca.19550380621Citations: 5AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat No abstract is available for this article. References p1490_1) H. Schmid, A. Ebnöther & P. Karrer, Helv. 36, 65 (1953). 10.1002/hlca.19530360111 CASWeb of Science®Google Scholar p1490_2) C. F. Garbers, H. Schmid & P. Karrer, Helv. 37, 1336 (1954). 10.1002/hlca.19540370440 CASWeb of Science®Google Scholar p1490_3) W. H. Perkin & J. F. Thorpe, J. chem. Soc. 85, 128 (1904). 10.1039/ct9048500128 CASWeb of Science®Google Scholar p1490_4) J. Amer. chem. Soc. 77, 251 (1955). 10.1021/ja01606a095 CASWeb of Science®Google Scholar Citing Literature Volume38, Issue61955Pages 1490-1490 ReferencesRelatedInformation

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Helvetica Chimica ActaVolume 37, Issue 1 p. 382-382 Article Über die Vitamin-A-Wirkung des cis-β-Carotins C (mit behinderter Doppelbindung) C. F. Garbers, C. F. Garbers Zürich, Chemisches Institut der UniversitätSearch for more papers by this authorC. H. Eugster, C. H. Eugster Zürich, Chemisches Institut der UniversitätSearch for more papers by this authorP. Karrer, P. Karrer Zürich, Chemisches Institut der UniversitätSearch for more papers by this author C. F. Garbers, C. F. Garbers Zürich, Chemisches Institut der UniversitätSearch for more papers by this authorC. H. Eugster, C. H. Eugster Zürich, Chemisches Institut der UniversitätSearch for more papers by this authorP. Karrer, P. Karrer Zürich, Chemisches Institut der UniversitätSearch for more papers by this author First published: 1954 https://doi.org/10.1002/hlca.19540370148Citations: 4AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article.Citing Literature Volume37, Issue11954Pages 382-382 RelatedInformation

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The identification of tetramethyl 1 -(methylthio)hexa-1,5-diene-2,3,4,5-tetracarboxylate (X), formed in low yield during attempted oxidation of dimethyl α-(bromomethyl)fumarate (IV) by dimethyl sulphoxide in the presence of a weak base, is described. It is shown that the production of the vinyl sulphide (X) under these conditions takes place via the intermediate (2,3-bismethoxycarbonylprop-2-enyl)dimethylsulphonium bromide (XIV), which undergoes a stereospecific Michael addition reaction with the derived sulphonium ylide (XX).

The structure of kitol (5), a natural retinol dimer, has been determined. Kitol was converted into a perhydro-cis-γ-lactone (20), suggesting cis-orientation of its two hydroxymethyl groups. Three model compounds were obtained by the Diels–Alder reaction of retinol acetate with methyl trans-β-formylcrotonate (9).

Methyl trans-β-formylcrotonate gave Diels–Alder adducts with 3-methylpenta-trans-2,4-dien-1-ol and 3-methyl-penta-trans-2,4-dienyl acetate. The structures of the adducts were determined by their conversion into the corresponding γ-and δ-lactones. A novel rearrangement of a trans-γ-lactone to a cis-γ-lactone is described.

The individual educator and her or his conduct are of central importance to the delivery of a quality basic education. This calls for a clear and co-ordinated response to address and prevent inappropriate educator conduct. Three broad deficiencies in current education legislation are identified. First, legislation provides for two types of educator, two different employers and two different sets of rules applicable to educator conduct in the same workplace. Secondly, the rules regulating the conduct of departmental educators contain an inappropriate legislative distinction between and description of ‘serious misconduct’ and ‘misconduct’, an unnecessary range of sanctions between a final written warning and dismissal and deficiencies in procedure. Thirdly, despite a clear overlap between the responsibilities of the employers of educators and the professional body for education, there is inadequate alignment between their roles, while gaps remain. The analysis relies not only on the provisions of the legislation itself, but also statistics and arbitration awards emanating from the Education Labour Relations Council. We argue that education legislation fosters an inappropriate managerial response to educator misconduct and suggestions for improvement are made.

This article explores the impact of education legislation on the failure to adequately address sexual misconduct by educators toward learners in South African public schools. The Employment of Educators Act 76 of 1998 is the central piece of legislation regulating the employment of departmental educators. Secs. 17and 18 of the EEA are analysed with reference to 48 arbitration awards issued by the Education Labour Relations Council. Three shortcomings are identified. First, the EEA describes the types of misconduct with which educators may be charged, but makes a distinction between “serious misconduct” listed in sec.17 (which attracts mandatory dismissal) and “misconduct” in sec. 18 (where dismissal is discretionary). The only two types of sexual misconduct expressly listed in sec. 17 of the EEA are sexual assault and sexual relationships with learners. Relevant arbitration awards show that other types of sexual misconduct encountered in public schools are often as serious. Secondly, the failure to expressly mention more types of sexual misconduct in the EEA (for example, sexual harassment and sexual grooming) often results in charges against educators based on catch-all provisions in the EEA such as “improper conduct”. This sanitises the seriousness and high incidence of certain types of sexual misconduct. In turn, it has two detrimental effects on the effective management ofsexual misconduct. Educators who are guilty of the types of sexual misconduct omitted from the EEA are not always dismissed. It also prevents proper recording and recognition of the systemic nature of specific types of sexual misconduct. Thirdly, sec. 18(3) of the EEA provides for a range of sanctions (notably fines) between a final warning and dismissal, and for the imposition of a combination of sanctions short of dismissal. This results in educators not beingdismissed, despite being guilty of serious sexual misconduct. The article argues for the express inclusion and description – in sec. 17 of the EEA – of a broader range of types of sexual misconduct often encountered in schools and for a change in approach to how sanction for misconduct is regulated by sec. 18(3) of the EEA. This will assist role players in correctly identifying the types of sexual misconduct involved, will lead to more consistent and appropriate charges against offenders, will result in more appropriate (and serious) sanctions imposed, and will provide clarity about the incidence of different types of educator sexual misconduct as the basis for further policy responses.

Cucurbitacin A has been transformed into C(9)–C(10)–C(19) cyclopropane derivatives. By ring opening under anionic conditions the primary C(9)β-CH2OH group of cucurbitacin A has, in effect, been shifted and reduced to give a 10β-methyl group. A remarkable hydroxy-group participation in a carbanionic process is an essential element in the fission of the cyclopropane ring. By appropriate manipulation of the oxidation levels of the intermediates in this process, cucurbitacin A has been converted into 4,4,14α-trimethylpregn-8-ene-2,7,11,20-tetra-one, identical with authentic material prepared from the degradation of eburicoic acid. In this way the constitutions assigned to all the cucurbitacins have been confirmed. In addition, this work gives proof of the stereochemistry of the cucurbitacins at C-9, C-13, and C-14.

This contribution reflects on the prohibition of unfair discrimination and affirmative action in South Africa. The prohibition of unfair discrimination in the Employment Equity Act is analysed in the light of developments at an international level and in the light of a comprehensive survey of South African jurisprudence. Based on this analysis, the authors conclude that the constraints associated with any prohibition of unfair discrimination, as borne out by the South African experience, inhibit the contribution that the prohibition and affirmative action can make towards the pursuit of substantive equality. Building on this analysis, affirmative action is placed under the spotlight in the second part of the contribution. As a redistributive strategy, affirmative action specifically attaches socio-economic benefits, such as jobs or government contracts, to those disadvantaged by status. However, this raises a number of important challenges, three of which are explored in this contribution. Questions are raised about the relationship between affirmative action and social identity, the demarcation of beneficiaries, and the potential impact of affirmative action measures.

Various C19 analogues of retinoic acid have been prepared from isopropyl t-butyl ketone. Potassium hydrogen sulphate in dimethyl sulphoxide proved an effective reagent for the elimination of water from intermediate hydroxyderivatives, but dehydration of 9-hydroxy-6,10-dimethyl-9-t-butylundeca-3,5,7-trien-2-one yielded 2-methyl-5-(4-isopropyl-1,5,5-trimethylhexa-1,3-dienyl)furan and 9-isopropyl-6,9,10-trimethylundeca-3,5,7,10-tetraen-2-one.

This contribution considers the legislative regulation of the job security (which boils down to preservation of employment) of employees in case of financial distress of a company. It juxtaposes the legislative regulation of four interrelated processes a company may engage in where it finds itself in financial distress, namely a voluntary internal restructuring (especially retrenchment), the transfer of the business or part of the business, business rescue and winding up. The legislative endeavour to preserve the job security of employees in all these processes is described and analysed. The discussion shows that room exists for companies to circumvent this protection and, to the extent that the protection does apply, that it remains difficult for employees to ultimately challenge the substance of decisions negatively affecting their job security. The main protection for employees in all these processes is procedural in nature and to be found in their rights to be informed of and consulted prior to decisions negatively affecting them. In this regard, business rescue is the most employee-friendly process. Participation in this process by employees, however, requires a fine balance as it may be self-defeating and lead to winding up and the permanent loss of jobs.

Formation of a stable sulphur ylide (III) during attempted oxidation of dimethyl γ-bromomesaconate by dimethyl sulphoxide is described.

An analysis of different methods of dealing with the application of domestic legislation in international employment disputes in the chosen jurisdictions indicates that two broad approaches are followed, namely a private international law approach and an interpretive approach. It is recommended that South Africa should follow a combination of these approaches, as is done in Britain, instead of the strict interpretive approach followed currently. This would entail that in deciding whether legislation is applicable, the court should take connecting factors into consideration. More specifically, it is further recommended that the definition of employee in the Code of Good Practice: Who is an Employee? be amended to provide guidelines to the Labour Court and the CCMA regarding connecting factors.

Methyl trans-β-formylcrotonate (2) and 4-hydroxy-3-methylbut-2-en-4-olide (cis-β-formylcrotonic acid) gave Diels–Alder adducts with dimethylbuta-1,3-diene with preservation of the steric arrangement of the substituents on the dienophile. The dienophile (2) similarly gave adducts with the 1,2,4-trisubstituted diene, 6,6-ethylenedi-oxy-3-methylhexa-2,4-dienyl acetate, which might prove of value in the synthesis of kitol-like dimers of retinol.

A trilogy of recent decisions emanating from the Labour Appeal Court, the Supreme Court of Appeal and the Constitutional Court respectively, serve both to highlight and confirm the opportunities for forum shopping that currently exist in labour disputes.

Collective labour law and the primary relationship it seeks to describe (between employers and trade unions) are not easy to come to grips with - not too many lawyers actually deal with it (except perhaps the odd strike interdict), students conceptually have little feeling for it, and ordinary persons often see it as a moral insult large enough to awaken all their prejudices.

Labor Rights Case Law covers noteworthy recent cases and decisions associated with fundamental labor standards and related internationally recognized core workers' rights.Different types of judicial and quasi-judicial bodies and mechanisms deal with the ilo's standards on child labor, forced labor, freedom of association, equal treatment, and occupational safety and health.This edition of ILaRC features a number of cases from what is sometimes referred to as the Global South.Three of these cases from international, regional, and national institutions are introduced here.

CITATION: Garbers, C. & Le Roux, P. 2018. Employment discrimination law into the future. Stellenbosch Law Review, 29(2):237-269.

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Abstract Der durch Kondensation von Isopropyl‐tert.‐butylketon mit Acetylen dargestellte Alkohol (Ia) wird in das Grignard‐Derivat übergeführt und anschlie‐ βend mit Buten‐(2)‐yliden‐aceton umgesetzt.

Abstract Das Erhitzen des trans‐Esters (I) mit dem Dien (II) in Gegenwart von Hydrochinon ergibt den trans‐Ester (III).

Abstract Diels‐Alder‐Reaktion von Retinolacetat (I) mit dem Crotonat (II) führt zu den Addukten (III)‐(V) im Verhältnis 23 220 : 7, deren Strukturen mit Hilfe ihrer Hydrolyseprodukte (VI)‐(VIII) bewiesen werden.

Abstract Der Aldehydester (II) reagiert mit dem trans‐Dienol (I) (in reinem Zustand oder im Gemisch mit dem cis‐Isomeren) zu den Addukten (III)‐(V) im Verhältnis 93 24:3.

Abstract Methacrylester (I) ergibt über eine Addition von Brom und nachfolgende Dehydrobromierung das Brom‐olefin (II), das mit Triphenylphosphin zum Salz (III) führt.

Chemischer InformationsdienstVolume 4, Issue 49 Preparative Organic Chemistry ChemInform Abstract: STEREOSPECIFIC FORMATION OF A VINYL SULPHIDE VIA A SULPHONIUM YLIDE-SALT COUPLING REACTION CHRISTOPH F. GARBERS, CHRISTOPH F. GARBERSSearch for more papers by this authorA. JOHAN H. LABUSCHAGNE, A. JOHAN H. LABUSCHAGNESearch for more papers by this authorCORNELIUS J. MEYER, CORNELIUS J. MEYERSearch for more papers by this authorDAVID F. SCHNEIDER, DAVID F. SCHNEIDERSearch for more papers by this author CHRISTOPH F. GARBERS, CHRISTOPH F. GARBERSSearch for more papers by this authorA. JOHAN H. LABUSCHAGNE, A. JOHAN H. LABUSCHAGNESearch for more papers by this authorCORNELIUS J. MEYER, CORNELIUS J. MEYERSearch for more papers by this authorDAVID F. SCHNEIDER, DAVID F. SCHNEIDERSearch for more papers by this author First published: December 4, 1973 https://doi.org/10.1002/chin.197349229Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume4, Issue49December 4, 1973 RelatedInformation

Abstract Isopren (I) reagiert mit den Chlormethyläthern (II) zu den Addukten (III), aus denen mit tert.‐Butylat die Diene (IV)‐(VI) gebildet werden.

Abstract Isopren (I) liefert mit HCI/Cyanidionen das Nitril (IIa), das zu (IIb) versei‐ft und zu (IIc) verester wird.

Abstract Bei der Umsetzung mit Dichlormethyl‐methylether (II) reagieren die Olefine (Ia) und (Ib) zu den Addukten (III).

Ladies and gentlemen, it is indeed a great privilege and pleasure for me to present the opening address at this, the 17th International Congress on High Speed Photograpy and Photonics. Before turning to the business of the Congress, I would like to briefly introduce you to South Africa: its scientific past and its research challenges for the future.