Pack-in-place column packing methods were developed for Q Sepharose Big Beads at 40 cm I.D. and scaled up to 200 cm I.D. in Chromaflow columns. The efficiency and asymmetry of the packed bed were evaluated as a function of test velocity and sample volume. The performance of the packed beds at both scales approached the theoretical limits of column performance (Hred =2 and Af=1) expected in small analytical columns. The packing strategy was effective for scale up and the stability of the packed beds, the effectiveness of the column design with respect to the mobile phase distribution system and the stability of the media to the pack-in-place technology, are presented.

Optimization of a 2-step reaction sequence was accomplished in 3-4 days, with over 200 different reaction conditions evaluated. Combinatorial arrays were performed using the optimized conditions to synthesize 590 new compounds which were tested for inhibition against N-His (D381E) ICE. Thirty-five compounds showed at least a tenfold improvement in activity compared to an initial standard.

Affinity chromatography is one of the most powerful and selective separation methods available. Recently, affinity methods are being incorporated into industrial processes with some frequency. One of the reasons for this is that affinity media robust enough for industrial bioprocessing are now available. By robust is meant that the media meet stringent requirements for cleanability, sanitization, physical and chemical stability, regulatory and technical support, batch-to-batch reproducibility and reliability of supply. This paper describes a medium format enhancement program to adapt a widely known group-specific affinity medium, Heparin Sepharose CL6B, to the requirements for industrial bioprocessing. The new medium, Heparin Sepharose 6 Fast Flow was designed for the recovery of antithrombia 3 (AT3) at industrial scale. The medium is based upon a highly cross-linked 6% agarose, which is produced in very large scale and is familiar to regulatory agencies. The ligand, heparin, is attached to the matrix by a reductive amination chemistry. The resulting linkage is stable in 0.1 N NaOH for 150 h, showing no decrease in AT3 binding affinity at that time. Heparin has a broad biological functionality and thus is useful chromatographically for the purification of a number of proteins which have an affinity for heparin. Heparin, as a complex sugar, is also a highly charged polyanion and thus has interesting ion-exchange properties. Because of its broad applicability to a number of purification problems, immobilized heparin is a useful case study in medium format enhancement.

Automated liquid handling workstations for performing combinatorial organic sytheses are recent additions to the organic laboratory Many of these robots are modifications of those used for biological work. Much of the recent literature describing these newly developed machines have focused on hardware.Described herein is a software suite, ACID, which has been developed for the Tecan(TM). This software arose from a need to simplify a typical organic chemist's interaction with the liquid handling robots performing parallel synthesis, Frier to this, much of the available software had been designed for biological work in which most samples are treated identically. Pt is the definition of combinatorial work that all samples are treated differently, hence a new approach was needed.The 20 programs written for ACID consist of four basic groups: Reactions, Extractions, Chromatography and Archival, The user launches a program within Integrator(TM) and is presented with a series of menus specific to that program. This program then creates a command file. ACID then uses a single program to read and interpret the command file for the Tecan(TM). In the course of the the execution of this prgram a log file and an error file are generated. Programs executing reactions also generate a tag file which describes the synthetic history of well locations. The tag file provides the link to the SD file containing structures.

This unit discusses the important parameters in designing and optimizing a separation by hydrophobic interaction chromatography (HIC), including preparing the sample and choosing a matrix, column, and buffer. Protocols are provided for packing and testing a column; determining binding and elution conditions; eluting the sample; and cleaning, regenerating, and storing HIC columns.

ChemInformVolume 18, Issue 13 Preparative Organic Chemistry ChemInform Abstract: Organoboron Compounds in Organic Synthesis. Part 3. Mechanism of Asmmetric Reduction of Dialkyl Ketones with (R,R)-2,5-Dimethylborolane. S. MASAMUNE, S. MASAMUNE Dep. Chem., MIT, Cambridge, MA 02139, USASearch for more papers by this authorR. M. KENNEDY, R. M. KENNEDY Dep. Chem., MIT, Cambridge, MA 02139, USASearch for more papers by this authorJ. S. PETERSEN, J. S. PETERSEN Dep. Chem., MIT, Cambridge, MA 02139, USASearch for more papers by this authorK. N. HOUK, K. N. HOUK Dep. Chem., MIT, Cambridge, MA 02139, USASearch for more papers by this authorY. WU, Y. WU Dep. Chem., MIT, Cambridge, MA 02139, USASearch for more papers by this author S. MASAMUNE, S. MASAMUNE Dep. Chem., MIT, Cambridge, MA 02139, USASearch for more papers by this authorR. M. KENNEDY, R. M. KENNEDY Dep. Chem., MIT, Cambridge, MA 02139, USASearch for more papers by this authorJ. S. PETERSEN, J. S. PETERSEN Dep. Chem., MIT, Cambridge, MA 02139, USASearch for more papers by this authorK. N. HOUK, K. N. HOUK Dep. Chem., MIT, Cambridge, MA 02139, USASearch for more papers by this authorY. WU, Y. WU Dep. Chem., MIT, Cambridge, MA 02139, USASearch for more papers by this author First published: March 31, 1987 https://doi.org/10.1002/chin.198713132Read 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 onEmailFacebookTwitterLinkedInRedditWechat No abstract is available for this article. References S. MASAMUNE, R. M. KENNEDY, J. S. PETERSEN, K. N. HOUK, Y. WU, Organoboron Compounds in Organic Synthesis. Part 3. Mechanism of Asmmetric Reduction of Dialkyl Ketones with (R,R)-2,5-Dimethylborolane., J. Am. Chem. Soc., 1986, 108, 7404. DOI: 10.1021/ja00283a043; 10.1021/ja00283a043 CASWeb of Science®Google Scholar Volume18, Issue13March 31, 1987 ReferencesRelatedInformation

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTReactions of Hydrocarbons Induced by Alkyl Fluoride Boron Trifluoride. IV. Stoichiometry of the Self-alkylation of IsobutaneConard K. Donnell and Robert M. KennedyCite this: J. Am. Chem. Soc. 1952, 74, 16, 4162–4164Publication Date (Print):August 1, 1952Publication History Published online1 May 2002Published inissue 1 August 1952https://pubs.acs.org/doi/10.1021/ja01136a061https://doi.org/10.1021/ja01136a061research-articleACS PublicationsRequest reuse permissionsArticle Views42Altmetric-Citations2LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

The barriers hindering internal rotation of methyl groups can be calculated by assuming that they are solely due to repulsion between hydrogen atoms according to the law Vij=4.99 ×105/rij5. For dimethyl ether, dimethyl sulfide, and propylene the empirically calculated values are low. This discrepancy is discussed. This treatment is applied to ethyl and isopropyl alcohol and several normal paraffins. The resulting entropies, heat capacities, and equilibrium constants are compared with the available experimental data.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTThe Heat Capacity and Entropy, Heats of Fusion and Vaporization, and the Vapor Pressure of Dimethyl Ether. The Density of Gaseous Dimethyl EtherR. M. Kennedy, Malcolm Sagenkahn, and J. G. AstonCite this: J. Am. Chem. Soc. 1941, 63, 8, 2267–2272Publication Date (Print):August 1, 1941Publication History Published online1 May 2002Published inissue 1 August 1941https://pubs.acs.org/doi/10.1021/ja01853a068https://doi.org/10.1021/ja01853a068research-articleACS PublicationsRequest reuse permissionsArticle Views803Altmetric-Citations81LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTHINDERED INTERNAL ROTATION OF METHYL GROUPS: THE ENTROPY OF SILICON TETRAMETHYLJ. G. Aston and R. M. KennedyCite this: J. Am. Chem. Soc. 1940, 62, 9, 2567Publication Date (Print):September 1, 1940Publication History Published online1 May 2002Published inissue 1 September 1940https://pubs.acs.org/doi/10.1021/ja01866a511https://doi.org/10.1021/ja01866a511research-articleACS PublicationsRequest reuse permissionsArticle Views41Altmetric-Citations3LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts