Bienal de Química: Síntesis orgánica, historia, glicobiología y ribosomas.
La tercera jornada de la XXXIII Reunión Bienal de la RSEQ fue muy intensa. Asistí a dos conferencias plenarias, dos conferencias invitadas, tres comunicaciones de póster seleccionados y a una sesión de presentaciones flash. Los temas fueron variados: metodológía sintética, moléculas complejas de quiralidad plana, interacciones carbohidrato-proteína, historia de la química y la toxicología, y ribosomas, RNA, proteínas y su significado biológico. Los resúmenes y mis impresiones se indican a continuación,
El día 27 de julio comenzó con la conferencia plenaria del profesor Gregory Fu (MIT), que expuso resultados de reacciones de acoplamiento catalizadas por paladio. Describió el acoplamiento de haluros de alquilo con alquilboranos catalizado por paladio (0) en presencia de fosfinas sencilla con impedimento estérico. Se puede partir de la olefina, la cual se hidrobora al borano. El método se aplica a tosilatos y a electrófilos alquílicos secundarios, realizándose estudios mecanísticos. Describió reacciones de Suzuki de haluros secundarios con organozincicos catalizado por complejos de níquel. En presencia de fosfinas quirales se obtuvieron altos rendimientos y buenos excesos enantioméricos. El método se aplicó a la síntesis de productos naturales. También se describieron reacciones de Suzuki con bromuros de alquilo secundario catalizadas por complejos de níquel. El estudio mecanístico de la reacción indica que es es de orden uno en borano y en catalizador y de orden cero en el electrófilo. Describió reacciones tandem de alquilboración y acoplamiento de Suzuki y su aplicación en síntesis asimétrica usando ligandos quirales (diaminas); así como reacciones de Suzuki dirigida por un sustituyente del sustrato. Otros resultados descritos fueron la reacción de Negishi de haluros de propargilo y arilzinc, la reacción de Hiyama (trialcoxisilanos como núcleofilos promovida por diaminas quirales y la aplicación de la reacción de Suzuki catalizada por níquel a la resolución cinética de α-cetoamidas. Esta resolución cinética no es demasiado eficiente (E = 1’8). Este resultado se explica por la formación de un radical y la baja selectividad se debe a la etapa de adición oxidativa.
En definitiva, Fu mostró un amplio repertorio de reacciones de utilidad sintética; pero demasiado metodológico. En mi opinión hubo una diferencia sustancial con la conferencia de Hartwig (en el fondo y la forma). Mientras que los dos explicaron “química” muy similar, Hartwig fue mucho más didáctico, explicando la base del diseño de las reacciones y haciendo una exposición dónde se apreciaba el desarrollo de las ideas. La charla de Fu fue una exposición de muchos resultados experimentales útiles, pero sin explicar los fundamentos del desarrollo del proyecto.
Una copia del resumen se puede descargar aquí.
En el simposio de Didáctica e Historia de la Química, el profesor José R. Bertomeu (Universidad de Valencia) impartió una conferencia invitada sobre la vida y obra de Mateu Orfila (1787-1853), que ha sido objeto de un libro reciente editado por el conferenciante. Me gustó mucho la conferencia, tanto por el personaje histórico (posiblemente el “padre” de la toxicología química) como por la exposición realzada por Bertomeu. Aparte de numerosos detalles humanos y científicos de Orfila, el conferenciante puso en contexto histórico los hechos; haciendo hincapié en aspectos sociales de la época. Es bien conocido que en esa época, el uso de venenos era bastante frecuente, especialmente el arsénico; por lo que Orfila se especializó en la determinación de venenos; siendo la máxim autoridad de la época. En mi twitter he recomendado la lectura de The Elements of Murder. A History of Poison, de Emsley. También recomiendo The Arsenic Century: How Victorian Britain was Poisoned at Home, Work, and Play, de Whorton. Debido a que la siguiente conferenciante de esta sesión no se presentó, la conferencia y discusión con Bertomeu se pudo prolongar un poco más.
Una copia del resumen de la conferencia de Bertomeu se puede descargar aquí.
La siguiente conferenciante plenaria fue Ada Yonath (Weizmann Institue of Science), Premio Nobel de Química en 2009. La conferencia fue espectacular, tanto desde el punto de vista formal como del fondo; describiendo muchísimos resultados experimentales y lanzando hipótesis interesantes. Partiendo del dogma central de la biología molecular (DNA a RNA a proteína), presentó a los ribosomas como la fábrica que produce proteínas continuamente a través de la descodificación de la información genética. Los ribosomas son universales. Una célula de mamífero puede contener millones de ribosomas. En una bacteria en reposo pueden existir 100000. La eficacia de los ribosomas es impresionante: generan de 15 a 40 enlaces peptídicos por segundo, prácticamente sin errores. Expuso con detalle (incluso ayudándose de videos) la traducción a nivel molecular. Posteriormente se centró en el estudio estructural de los ribosomas, identificando al RNA como la molécula fundamental para el funcionamiento del ribosoma. Estos hechos parecen confirmar la hipótesis de que, evolutivamente, el RNA fue anterior a las proteínas (la hipótesis del mundo-RNA). El RNA no es un catalizador eficiente pero sí es una eficaz máquina de hacer proteínas. Desde el punto de vista estructural, existe simetría en la subunidad mayor del ribosoma, un hecho muy interesante, y además está muy conservada evolutivamente. Yonath explicó que las moléculas de RNA tiene las siguientes propiedades: autoreplicante, autoplegables y autodimerizables con capacidad catlítica.
Evolutivamente, propone que existió un protorribosoma, que fue una enzima dimérica producida por duplicación o fusión de genes. Esta hipótesis tiene importates implicaciones en el mundo prebiótico y recordó que la función es superior a secuencia desde un punto evolutivo (algo ya conocido en enzimología). A continuación pasó a discutir el posible origen del código genético. Yonath propone la hipótesis de que en origen del ancestro del código genético el protorribosoma jugó un papel fundamental. Con actividad catalítica, los sustratos del protorribosoma pudieron ser dipéptidos y estos eligieron el codón que les codificaba (posiblemente a través de interacciones no covalentes). Especula sobre los posibles primeros aminoácidos en la evolución: ¿glicina, alanina?, por ser los más sencillos; ¿histidina?, por su capacidad catalítica; ¿lisina, arginina?, por ser básicos; ¿fenilalanina, triptófano?, por ser aromñaticos; etc. En definitiva, los ribosomas son moléculas ancestrales y usan proteínas para ser máquinas más eficaces de fabricación de proteínas.
En la última parte de la conferencia se centró en el diseño de antibióticos que actúan por inhibición de la síntesis de proteínas en el ribosoma. Debido a que estas estructuras celulares están muy conservadas evolutivamente, es difícil tener fármacos selectivos que actúen sólo sobre el microorganismo y no sobre el anfitrión. Estos fármacos (por ejemplo, cloranfenicol, clindomicin, eritromicina o azitromicina) o son naturales o están inspirados en la naturaleza. Los microorganismos usan los antibióticos naturales como armas para defenderse de otros microorganismos. El mecanismo de acción de estos compuestos es deteniendo la función del ribosoma uniéndose a sitios fundamentales del mismo.
Aunque la conferencia fue más larga de lo previsto (80 minutos), disfruté escuchándola, pues aprendí muchísimo. No hay copia del resumen de la conferencia en el libro de resúmenes.
La sesión de tarde la comencé asistiendo a la ponencia de la Dra. Sonsoles Martín-Santamaría (Universidad San Pablo-CEU), póster seleccionado en el simposio de Química Biológica. Expuso resultados sobre las interacciones carbohidrato-proteína, analizando las bases moleculares de esta interacción por una combinación de métodos experimentales y computacionales. También presentó resultados de la interacción de oligosacáridos con catión calcio.
Una copia del resumen de la comunicación se puede descargar aquí.
Posteriormente asistí a las presentaciones flash del simposio de Didáctica e Historia de la Química; donde se presentaron comunicaciones sobre el uso el ordenador en resolución de problemas; el centenario de la conferencia Solvay y la física moderna; herramientas informáticas para prevención de riesgos laborales en el laboratorio de química analítica; y Robert Bunsen como innovador.
A continuación Jesús Arsuaga (Universidad Rey Juan Carlos) impartió una comunicación seleccionada sobre los orígenes de la química física, desde Lavoisier a Pauling; con una visión muy particular sobre este asunto. Hubo una intensa discusión sobre estos orígenes y el papel que otros científicos han hecho en esta disciplina y la relación con otras áreas de la química y de la física. Creo que fue una incorporación de última hora al programa y no hay resumen de la comunicación en el libro de resúmenes.
A continuación asistí a la entrega de los premios y la proyección de los videos del concurso Reacciona, una iniciativa de la RSEQ-STV, en colaboración con las dos universidades valencianas y la Ciudad de las Artes y las Ciencias. Los videos ganadores, realizados por alumnos de ESO-Bachillerato o universitarios, tenían un contenido muy adecuado y una realización cuidada. Los videos los podéis descargar de youtube.
La última conferencia invitada del día corrió a cargo de la profesora Mª Carmen Carreño (Universidad Autónoma de Madrid). Siempre es un placer escuchar a Carmen Carreño, por lo bien que explica su investigación, que es muy interesante y original. Su conferencia trató principalmente sobre ferroceno[4]helienoquinona; que son compuestos con quiralidad plana que pueden tener aplicaciones tecnológicas. Se obtienen por resolución cinética a través de reacciones de Diels-Alder con sulfóxidos quirales. También describió la síntesis de ácidos borónicos derivados de quinonas y su aplicación a la la reacción de Diels-Alder, dónde se produce una desborilación que puede tener utilidad sintética; de esta manera, el grupo dihidroxiborano (ácido borónico) es un controlador sintético útil. Finalmente, se describieron las aplicaciones de quinoles en síntesis de productos naturales.
Una copia del resumen de la conferencia se puede descargar aquí.
Bernardo Herradón-G.
CSIC
Halfway through I knew I would finish the post, and a stop at actionactivation also held me through to the end, content that signals its quality early and then sustains it is content with real internal consistency and this site has clearly figured out how to maintain quality from opening sentence through to closing thought.
Skipped the comments section but might come back to read it, and a stop at ideasneeddirection hinted at a quality reader community, sites where the comments are worth reading separately from the post are increasingly rare and signal a particular kind of audience that has grown around the editorial vision over time gradually.
Really appreciate the confidence to make a clear point rather than hedging everything, and a quick visit to ideaorchestration maintained the same direct stance, writing that takes positions rather than equivocating is more useful even when the positions are debatable because at least the reader has something to react to clearly.
Will share this on a forum I am part of where it will be appreciated by others working in the same area, and a look at trustednetworkcircle suggests there is more here worth passing along too, definitely a generous resource that deserves a wider audience than it probably has today across the open internet.
Once you find a site like this the search for similar voices begins, and a look at strategymap extended the search energy, finding a high quality reference point makes the gap between it and adjacent sources visible in a way it was not before and this site has provided that high reference point across multiple recent visits.
Really thankful for posts that respect a reader’s time, this one does, and a quick look at strongconnectionalliance was the same, no need to scroll through endless intros just to get to the actual content, that approach alone is enough reason to come back here regularly for the kind of writing offered.
Even across multiple posts the writers voice has remained consistent in a way I appreciate, and a stop at primecapitalbond continued that voice, sites that maintain editorial consistency across many pieces have something most sites lack and this one has clearly worked out how to keep its voice steady across what reads as a growing archive.
Honestly this kind of writing is why I still bother to read independent sites, and a look at ideasflowintoaction extended that broader reflection, the few sites that justify continued attention to non algorithmic content are sites like this one and finding them periodically is enough to keep my reading habits oriented toward independent rather than aggregated content.
Just want to recognise that someone clearly cared about how this turned out, and a look at forwardmotionengine confirmed that care extends across the broader site, you can feel the difference between content shipped to hit a deadline and content released because the writer was actually proud of the result for once.
Now understanding why someone recommended this site to me a while back, and a stop at bondedtrustpath explained the recommendation, sometimes recommendations make sense only after experience and this site has finally clicked into place as the kind of resource I now understand was being recommended for sound editorial reasons by my friend.
Closed several other tabs to focus on this one as I read, and a stop at focusleadsdirection held my undivided attention the same way, content that earns full focus in an attention environment full of competing pulls is content doing something genuinely well and the team behind it deserves recognition for that achievement consistently.
Worth marking the moment when reading this clicked into something useful for my own work, and a look at progressneedsfocus extended that practical click, content that connects to my actual life rather than just being interesting is content with the highest kind of value and this site is generating that connection at a high rate.
A genuinely unexpected highlight of my reading week, and a look at progressmovespurposefully extended that pattern, the surprise of finding excellent content rather than the predictable mediocre is one of the few real pleasures of casual web browsing and this site delivered that surprise cleanly today which I really do appreciate.
Pass this along to colleagues if the topic comes up, the framing here is sensible, and a stop at focusmapping adds more useful angles to share, the kind of content that improves conversations rather than just feeding them is what makes a resource genuinely valuable in professional contexts going forward over time and across project boundaries too.
Held my interest from the opening line through to the closing thought, and a stop at focusanchorsmovement did the same, content that earns sustained attention in an environment full of distractions is doing something right and this site is clearly doing several things right rather than just one or two which I really appreciate.
Now appreciating that I did not feel exhausted after reading, and a stop at bondedprinciples extended that energising quality, content that leaves me with more attention than it consumed is rare and the gap between draining and energising content is real over the course of a typical day spent reading widely online.
Refreshing tone compared to the dry corporate posts on similar topics, and a stop at forwardmotionactivatednow carried that personality through nicely, you can tell when a real person is behind the writing versus a content team chasing metrics and this site definitely falls into the former category clearly across what I have seen.
Refreshing tone compared to the dry corporate posts on similar topics, and a stop at forwardmotionstructure carried that personality through nicely, you can tell when a real person is behind the writing versus a content team chasing metrics and this site definitely falls into the former category clearly across what I have seen.
Picked this for my morning read because the topic seemed worth the time, and a look at ideaconversion confirmed the choice was right, my morning reading slot is precious and giving it to this site felt like a good investment rather than a waste which is a higher endorsement than I usually offer for content.
Reading this triggered a small change in how I think about the topic going forward, and a stop at focuspowersprogress reinforced that subtle shift, the rare content that actually moves my thinking rather than just confirming or filling it is the kind I most value and this site is providing that kind of impact today.
Liked the way the post handled the final paragraph, no neat bow but no abrupt cutoff either, and a stop at globalunitygroup continued that thoughtful ending pattern, endings are hard and most blog writers either over engineer them or skip them entirely and this site has clearly figured out a sustainable middle approach.
Closed three other tabs to focus on this one and never opened them again, and a stop at unitedsuccesscircle similarly held attention exclusively, content that crowds out other reading from working memory is content with real density and this site has demonstrated that density across multiple pages I have visited so far this morning.
Halfway through I knew I would finish the post, and a stop at claritysystem also held me through to the end, content that signals its quality early and then sustains it is content with real internal consistency and this site has clearly figured out how to maintain quality from opening sentence through to closing thought.
Started reading and ended an hour later without realising the time had passed, and a look at actionorchestration produced the same time dilation effect, when content makes time feel different the writer has achieved something well beyond the average and this site is producing that experience for me reliably across multiple readings.
Walked away with a clearer head than I had before reading this, and a quick visit to clarityexecution only sharpened that, the writing has a way of cutting through the noise that surrounds most topics online which is something I will definitely remember the next time I am searching for an answer to anything.
Honestly thank you to whoever wrote this because it scratched an itch I had not quite been able to articulate, and a stop at growthtrustcircle kept that satisfying feeling going, the kind of writing that meets unspoken needs is special and this site clearly has writers who understand their readers more than most do today.
Quietly enthusiastic about this site after the past few hours of reading, and a stop at directionactivatesmotion extended that enthusiasm, the calibration of enthusiasm to evidence is something I try to maintain and this site has earned a calibrated quiet enthusiasm rather than the loud excitement that usually fades within a day or two of finding something.
Now thinking the topic is more interesting than I had given it credit for, and a stop at longviewalliance continued that elevated interest, content that revives my curiosity about subjects I had set aside is doing genuine work in the structure of my interests and this site is providing that revivifying effect today actually.
A piece that handled a controversial angle without becoming heated, and a look at solidbondgroup continued that calm engagement, content that can address contested topics without inflaming them is doing rare diplomatic work and this site has clearly developed the editorial maturity to handle sensitive material with the appropriate temperature of writing throughout.
Took a chance on the headline and was rewarded, and a stop at claritycompanion kept the rewards coming as I clicked through, the kind of place where every link leads somewhere worth the click is a small luxury on the modern web where so many sites are mostly empty calories disguised as content.
Recommended without reservation for anyone interested in the topic at any level of expertise, and a look at growthvector only strengthens that recommendation, this site clearly knows how to serve readers across a range of backgrounds without watering down the content or talking past anyone in the audience which is genuinely impressive to see.
Now considering writing a longer note about the post somewhere, and a look at ideasunlockmotion added more material for that note, content that prompts me to write rather than just consume is content with generative energy and this site is producing that generative effect for me at a higher rate than most sources.
Liked the careful selection of which details to include and which to skip, and a stop at actiondrivesmomentum reflected the same editorial judgement, knowing what to leave out is just as important as knowing what to include and this site has clearly figured out where that line sits for the topics it covers regularly.
Generally my attention drifts on long posts but this one held it through the end, and a stop at ideasdrivevelocity earned the same sustained focus, content that defeats my drift tendency is content with substantive pulling power and this site has demonstrated that pulling power across multiple pieces in a session that has now run quite long actually.
The examples really helped me grasp the points faster than abstract descriptions would have, and a stop at nextstepnavigator added a few more practical illustrations that drove the message home, the kind of writing that knows its readers learn better through concrete situations rather than vague generalities is rare and worth recognising clearly.
Worth flagging this site to a few specific friends who would appreciate the editorial sensibility, and a look at heritagecapitalbond added more pages I will mention to them, recommending sites to specific people requires understanding both the site and the person and this site is making those personalised recommendations easy and natural for me.
Люди помогите советом Кошмар полный Родственники в полной панике Платная клиника — выкачивает деньги Короче, спасла только госпитализация — вывод из запоя стационарно с капельницами Выписали через 5 дней здоровым В общем, вся инфа по ссылке — прокапаться от алкоголя в стационаре https://vyvod-iz-zapoya-v-staczionare-sankt-peterburg-wjf.ru Не ждите чуда Это может спасти жизнь близкого
Probably worth setting aside a longer block to read more carefully than I can right now, and a stop at strategyplanner confirmed the longer block plan, the impulse to schedule dedicated time for a sites archive is itself a measure of trust and this site has earned that scheduling impulse from me clearly today actually.
Reading this with a notebook open turned out to be the right move, and a stop at progressmomentum added more material to the notes, content that justifies active note taking from a passive reader is content with real informational density and this site is producing notes worthy material at a high rate consistently.
Glad I gave this a chance rather than scrolling past, and a stop at ideasunlockgrowth confirmed I made the right call, sometimes the best content is hidden behind unassuming headlines that do not scream for attention and learning to slow down and check those out has paid off many times now across years of reading.
Speaking as someone who reads a lot on this topic this site has earned a high position in my source rankings, and a stop at clarityanchorsmotion reinforced that ranking, the informal ranking of sources for a topic is something I maintain mentally and this site has moved into the upper portion of those rankings clearly.
Just want to recognise that someone clearly cared about how this turned out, and a look at strategicalliancelink confirmed that care extends across the broader site, you can feel the difference between content shipped to hit a deadline and content released because the writer was actually proud of the result for once.
Found the rhythm of the prose particularly enjoyable on this read through, and a look at signaldrivesclarity kept that musical quality going across the related pages, sentence rhythm is something most blog writers ignore but it makes a real difference in how content lands with the careful reader who cares.
Refreshing to find writing that does not try to manipulate the reader into clicking onto the next page through cliffhangers and forced engagement, and a stop at progressmoveswithsignal continued in the same respectful way, this is what reader first design actually looks like in practice rather than just in marketing copy that sounds nice.
Worth saying this site reads better than most paid newsletters I have tried, and a stop at forwardmomentumhub confirmed that comparison, the bar for free content is often lower than for paid but this site clears the paid bar consistently and that says something about the editorial approach behind the work being published here regularly.
Skipped the related products section because there was none, and a stop at actionmapping also lacked any aggressive monetisation, content that is not constantly trying to convert me into a customer or subscriber is content that has confidence in its own value and that confidence shows up as a different reading experience.
Worth marking the moment when reading this clicked into something useful for my own work, and a look at forwardprogression extended that practical click, content that connects to my actual life rather than just being interesting is content with the highest kind of value and this site is generating that connection at a high rate.
Now wishing more sites covered topics with this level of care, and a look at progressmovesintelligently extended that wish across more subjects, the rarity of careful coverage on most topics is a problem and this site is one of the small antidotes to that broader pattern of casual or surface treatment of complex subjects.
Now planning to recommend this site in a context where my recommendations are taken seriously, and a stop at momentumbuildsforward confirmed I should make that recommendation soon, the small but real act of recommending content into spaces where my taste matters is something I take seriously and this site is worth the recommendation.
During a quiet evening reading session this provided just the right depth without being heavy, and a stop at bondedpathway maintained the same evening appropriate weight, content with depth that does not exhaust the reader is content with editorial calibration and this site has clearly figured out how to be substantial without being demanding all the time.