Meta tags:

Headings (most frequently used words):

juillet, 2007, of, mercredi, chemistry, mardi, 10, synthesis, heterocyclic, 31, 18, vendredi, 13, jeudi, 12, 11, blogroll, qui, êtes, vous, archives, du, blog, group, meetings, course, neooxazolomycin, part1, hydroxyquinoline, vs, dimethoxy, phenantroline, lot, work, and, colorectal, cancer, mcr, barbiturate, neurogenesis, in, skeletal, muscle, total, iromycins, methyltryptamine,

Text of the page (most frequently used words):
the (93), and (37), with (27), synthesis (22), hetchem (15), this (15), 2007 (14), #chemistry (10), reaction (9), juillet (8), but (8), which (8), from (8), have (8), libellés (7), commentaires (7), publié (7), par (7), for (7), pyrone (7), are (7), acid (6), first (6), group (5), methyltryptamine (5), skeletal (5), muscle (5), very (5), interesting (5), after (5), not (5), ring (5), yield (5), using (5), been (5), will (5), synthesized (5), see (5), course (4), total (4), iromycins (4), neurogenesis (4), mcr (4), org (4), one (4), cyclization (4), pyridine (4), also (4), different (4), obtained (4), type (4), steps (4), guys (4), paper (4), imidazoles (4), phenantroline (4), ligand (4), stoltz (3), barbiturate (3), lot (3), work (3), colorectal (3), cancer (3), hydroxyquinoline (3), neooxazolomycin (3), articles (3), only (3), can (3), starts (3), michael (3), mercredi (3), small (3), concerning (3), has (3), same (3), pyridone (3), way (3), imidazole (3), cells (3), treatment (3), that (3), you (3), doi (3), carbodiimide (3), alkyl (3), 1equiv (3), step (3), indicates (3), arylation (3), benzimidazoles (3), lactam (3), lactone (3), organic (2), clubs (2), problems (2), dimethoxy (2), part1 (2), blog (2), chemist (2), chem (2), molecule (2), chemical (2), atom (2), indole (2), some (2), like (2), research (2), find (2), grandberg (2), indeed (2), formation (2), hydrazone (2), between (2), intermediates (2), provides (2), almost (2), scale (2), oprd (2), natural (2), product (2), today (2), post (2), starting (2), preparation (2), metabolites (2), biological (2), von (2), zezschwitz (2), reactions (2), followed (2), lda (2), provide (2), second (2), metalation (2), give (2), subsequent (2), lactonization (2), performed (2), furnish (2), realized (2), 120 (2), sealed (2), tube (2), through (2), addition (2), opening (2), presence (2), new (2), streptomyces (2), convergent (2), joc (2), mardi (2), furane (2), week (2), jacs (2), induce (2), upon (2), neuronal (2), shown (2), particular (2), view (2), substituents (2), support (2), platforms (2), below (2), derivative (2), classical (2), multicomponent (2), info (2), acs (2), 1021 (2), dealing (2), malonic (2), ester (2), yields (2), all (2), before (2), mixture (2), together (2), k2co3 (2), think (2), rss (2), end (2), buchwald (2), read (2), best (2), according (2), because (2), quite (2), isolated (2), pyrrole (2), dihydroxylation (2), moiety (2), hatakeyama (2), dmf (2), amide (2), was (2), heterocyclic (2), dave, macmillan, princeton, supergroup, phil, baran, literature, mechanism, theses, archive, crimmins, eavsn, seminar, ccb, challenging, fukuyama, metting, meetings, février, mars, avril, mai, juin, prenylindole, chloro, aminopyrazolylisoquinoline, phenantro, archives, afficher, mon, profil, complet, qui, êtes, vous, totallymedicinal, whistling, wind, organometallic, current, prep, daily, day, kinasepro, totallysynthetic, musings, pushers, syntheticenvironment, carbontet, carbon, based, curiosities, chembark, transition, state, curly, arrow, ten, thousand, blogroll, inscription, accueil, plus, anciens, tryptamine, people, probably, noticed, process, development, chemically, speaking, nothing, weird, classic, scalable, column, dream, sometimes, stuff, methodology, modified, fisher, phenylhydrazine, chloropentan, isomerization, iminium, enamine, form, rearrangment, takes, place, afford, tricyclic, loss, proton, 800l, reactor, joel, slade, david, parker, girgis, raeann, scott, joseph, oljan, repi, optimization, valuable, tool, diels, alder, microbial, exibit, activity, synthase, inhibitors, their, structures, fully, substituted, pyridones, recently, gottingen, germany, described, iromycin, analogues, via, cross, coupling, nucelus, construction, successive, condensation, material, ethyl, methyl, oxo, butanoate, lithiated, alkylated, propyl, iodide, acetylated, acetylimidazole, acetylating, agent, crude, employing, dbu, desired, hand, aqueous, ammoniac, dioxane, closure, procedure, interestingly, stepwise, hydrazine, intermediate, hydrolyzed, potassium, hydrogenolsulfate, supply, aminopyridone, diazotation, acetic, lead, tell, well, known, since, century, usual, clockwise, family, heydar, shojaei, zhen, hmer, paultheo, 5091, korean, published, human, neurodazine, c2c12, develop, phenotype, they, mouse, 20k, dna, chips, upregulated, gene, involved, inducing, differentiation, point, these, library, solid, wang, resin, amino, conjuguated, diethylene, glycol, more, than, 300, purity, three, polymer, supported, example, benzylamine, aldehyde, r1cho, dicarbonyl, compound, r2cocor3, ammonium, acetate, mainly, aromatic, compounds, other, tests, supporting, darren, williams, myung, ryul, lee, young, song, sung, kyun, gun, hee, kim, injae, shin, http, pubs3, journals, doilookup, in_doi, ja072817z, synthetic, molecules, pyrimidine, boss, italian, about, future, project, multi, component, barbiturates, unsymetrical, aryl, halides, lett, letter, 841, 844, ol063074, good, there, still, drawbacks, must, introduced, depending, needed, carbodiimides, third, racemic, sequential, mixed, overnight, acetonitrile, then, halide, 4equiv, were, added, heated, 30min, microwave, oven, 5min, jeudi, phtalazine, god, just, reader, 170, don, elsevier, feed, beach, friend, pierre, who, potent, vatalanib, tyrosine, kinase, inhibitor, should, market, 2008, sorry, vendredi, quinoline, 275, ryan, altman, erica, koval, stephen, copper, catalyzed, nevertheless, quickly, publication, abstract, conclusion, seems, excellent, choice, regioselectivity, methylimidazole, better, otherwise, cases, finally, reason, cheaper, nice, synthesize, phenantrolines, consists, methoxyalkylidene, meldrum, trimethylorthoformate, double, phenylene, diamine, perform, disubstituted, aminobenzene, thermal, decarboxylation, diphenylether, 250, dihydroxyphenantroline, chlorination, refluxing, pocl3, nucleophilic, substitution, naome, over, author, combination, procedures, most, relevant, following, tetrahedron, 2002, 9095, always, useful, last, jumped, directly, 326, interersting, reformatsky, stille, nozaki, hiyama, kishi, tamao, hydrosilylation, achieve, furo, present, heptynol, tetramethyldisilazane, hme2si, 2nh, hydromethylsilylether, dvds, catalyst, thf, gives, cyclic, siloxane, iodination, csf, meoh, iodoalkenol, continues, oxidation, alcohol, under, jones, conditions, carboxylic, condensed, methylamino, malonate, chloride, alkenyl, oac, pph3, couple, nbu4nbr, solution, results, alkylidene, pyrrolidinone, crucial, undoubtedly, stereoselective, oso4, nmo, concomitant, uemura, 1985, oxazolomycin, oxazole, polyene, antibiotics, 1990, kende, onyango, tsurumoto, imai, takahashi, ishihara, aciee, early, 1002, anie, 200702229,

Text of the page (random words):
heterocyclic chemistry heterocyclic chemistry mardi 31 juillet 2007 neooxazolomycin part1 onyango tsurumoto imai takahashi ishihara hatakeyama aciee 2007 early view doi 10 1002 anie 200702229 neooxazolomycin was isolated by uemura in 1985 together with the oxazolomycin this oxazole polyene lactam lactone antibiotics was synthesized first by kende in 1990 but i find interesting the way to achieve the synthesis of the furo pyrrole moiety lactam lactone by hatakeyama this synthesis i present you starts from the reaction of heptynol see below and tetramethyldisilazane hme2si 2nh provides hydromethylsilylether not shown which upon treatment with pt dvds as catalyst in thf gives the cyclic siloxane after iodination with i2 in presence of csf in a dmf meoh mixture the iodoalkenol is obtained in 82 3 steps the synthesis continues with the oxidation of the alcohol under jones conditions and the carboxylic acid is condensed with 2 methylamino malonate through the acid chloride to provide the amide in 62 yield 3 steps the cyclization of the alkenyl amide with the pd oac 2 pph3 couple k2co3 and nbu4nbr in solution in dmf results in the formation of the alkylidene pyrrolidinone in 84 yield the crucial step is undoubtedly the stereoselective dihydroxylation using oso4 nmo with a concomitant lactonization to furnish lactam lactone moiety in 88 yield a very interersting paper with a lot of different chemistry reformatsky stille nozaki hiyama kishi tamao hydrosilylation dihydroxylation publié par hetchem à 06 42 326 commentaires libellés furane hetchem natural product pyrrole mercredi 18 juillet 2007 8 hydroxyquinoline vs 4 7 dimethoxy 1 10 phenantroline i always read paper from buchwald not because it is interesting but it can be useful and in particular the last joc dealing with n arylation of imidazoles and benzimidazoles i jumped directly to the support info to see the synthesis of the phenantroline ligand the author indicates that the ligand has been synthesized according to a combination of procedures but the most relevant is the following one tetrahedron 2002 58 9095 the first step consists in the synthesis of the methoxyalkylidene derivative of meldrum s acid with trimethylorthoformate and a subsequent double michael addition of phenylene diamine to perform the disubstituted aminobenzene in 77 yield after a thermal decarboxylation cyclization in diphenylether at 250 c the 4 7 dihydroxyphenantroline is isolated in 86 the end of the reaction is quite classical a chlorination in refluxing pocl3 followed by a nucleophilic substitution with naome in 74 over 2 steps nice way to synthesize phenantrolines nevertheless if you read quickly this publication abstract and conclusion it seems this phenantroline is the best ligand for the n arylation of imidazoles and benzimidazoles according to me it is not of course this ligand is excellent but my first choice will be 8 hydroxyquinoline because first the regioselectivity concerning the 4 methylimidazole is better 63 1 otherwise in almost all the cases the yields are quite the same and finally the best reason it is cheaper copper catalyzed n arylation of imidazoles and benzimidazoles ryan a altman erica d koval and stephen l buchwald j org chem 2007 publié par hetchem à 00 57 275 commentaires libellés hetchem phenantroline quinoline vendredi 13 juillet 2007 lot of work and colorectal cancer oh my god i am just opening my rss reader it indicates 170 new articles and don t have elsevier rss feed so i think i will work this week end after the beach and a very small post for my friend pierre who indicates me a very potent molecule for the treatment of colorectal cancer the vatalanib a tyrosine kinase inhibitor and should be on the market in 2008 sorry today no chemistry publié par hetchem à 12 52 2 commentaires libellés hetchem phtalazine jeudi 12 juillet 2007 3 mcr of barbiturate my boss give me a paper from italian guys about my future research project dealing with the multi component synthesis of barbiturates using unsymetrical carbodiimide n aryl n alkyl carbodiimide malonic acid ester and an alkyl halides indeed it is a sequential multicomponent reaction which is performed in a sealed tube first carbodiimide 1 1equiv and malonic acid ester 1equiv are mixed together at rt overnight in acetonitrile 0 1m and then k2co3 2 1equiv and alkyl halide 4equiv were added and heated at 120 c for 30min i think i will do this step in the microwave oven for 5min the yields obtained with this type of reaction are between 52 and 90 which is good but there is still drawbacks first of all the r1 must be introduced before the mcr second depending on the substituents needed the carbodiimides have also to be synthesized before and third we have a racemic mixture org lett letter 2007 9 5 841 844 doi 10 1021 ol063074 publié par hetchem à 02 08 26 commentaires libellés barbiturate hetchem mcr pyrimidine mercredi 11 juillet 2007 neurogenesis in skeletal muscle this week in jacs korean guys have published a very interesting paper concerning the induce neurogenesis of human skeletal muscle cells upon neurodazine nz treatment of c2c12 cells skeletal muscle cells develop a neuronal phenotype they have shown also using a mouse 20k dna chips that nz upregulated in particular gene which is involved in inducing neuronal differentiation from a chemical point a view these guys have synthesized an imidazole library with different substituents in 1 2 4 and 5 on solid support wang resin with amino conjuguated diethylene glycol more than 300 imidazoles have been obtained with a purity 70 three different polymer supported platforms have been realized you will see below only one example using a benzylamine derivative the imidazole ring has been synthesized with the classical multicomponent reaction with an aldehyde r1cho an 1 2 dicarbonyl compound r2cocor3 and with ammonium acetate r1 r2 and r3 are mainly aromatic compounds to see the other platforms chemistry and biological tests see supporting info synthetic small molecules that induce neurogenesis in skeletal muscle darren r williams myung ryul lee young ah song sung kyun ko gun hee kim and injae shin jacs 2007 doi http pubs3 acs org acs journals doilookup in_doi 10 1021 ja072817z publié par hetchem à 12 25 13 commentaires libellés furane hetchem imidazole mardi 10 juillet 2007 total synthesis of iromycins today a small post concerning the synthesis of pyridone starting from pyrone which is not only a valuable tool in diels alder reaction but also for the preparation of pyridine ring iromycins are microbial metabolites which exibit an interesting biological activity as no synthase inhibitors their structures are fully substituted pyridones recently von zezschwitz et al from gottingen in germany described the synthesis of iromycin a and different analogues via cross coupling reaction this synthesis of the nucelus starts with the construction of the pyrone ring by successive condensation reactions followed by cyclization the starting material the ethyl 2 methyl 3 oxo butanoate 1 is lithiated by lda at 0 c and alkylated with propyl iodide to provide 2 in 56 yield a second metalation also with lda give the acetylated intermediates 3 using n acetylimidazole as acetylating agent the subsequent lactonization is performed on the crude employing dbu to furnish the desired 2 pyrone 4 the pyrone in hand the preparation of pyrone 4 has been realized with aqueous ammoniac in dioxane at 120 c in a sealed tube through a 1 6 michael addition ring opening ring closure procedure in 75 interestingly the same pyridone can be obtained by a stepwise way with the same type of reaction in presence of hydrazine the intermediate hydrazone 5 is hydrolyzed with potassium hydrogenolsulfate to supply the n aminopyridone 6 the diazotation of 6 in acetic acid lead to the 2 pyrone in 88 on 2 steps of course some guys will tell me this type of reactions are well known since century but i like this type chemistry this is not the usual clockwise metalation of pyridine or synthesis of pyridine by da reaction iromycins a new family of pyridone metabolites from streptomyces sp ii convergent total synthesis streptomyces sp ii convergent total synthesis heydar shojaei zhen li bo hmer and paultheo von zezschwitz joc 2007 72 5091 publié par hetchem à 12 03 2 commentaires libellés hetchem natural product pyridine pyrone mercredi 4 juillet 2007 synthesis of 2 methyltryptamine as some people probably noticed i like oprd organic process research development of course chemically speaking nothing weird only classic chemistry but scalable synthesis and no column for me the dream and sometimes we can find very interesting stuff as this synthesis of the 2 methyltryptamine by the grandberg methodology which is indeed a modified fisher indole synthesis this chemistry starts with the formation of the hydrazone between the phenylhydrazine and the 5 chloropentan 2 one after cyclization and isomerization from iminium to enamine form the rearrangment takes place to afford the tricyclic intermediates which after loss of a proton provides the 2 methyltryptamine with 42 in almost 20 kg scale in a 800l reactor optimization and scale up of the grandberg synthesis of 2 methyltryptamine joel slade david parker michael girgis raeann wu scott joseph and oljan repi oprd 2007 publié par hetchem à 13 14 47 commentaires libellés hetchem indole tryptamine articles plus anciens accueil inscription à articles atom blogroll one in ten thousand curly arrow chemist in a transition state chembark carbon based curiosities carbontet syntheticenvironment atom pushers chemical musings totallysynthetic kinasepro molecule of the day org prep daily organometallic current the chem blog whistling the wind totallymedicinal qui êtes vous hetchem chemist afficher mon profil complet archives du blog 2007 33 juillet 9 neooxazolomycin part1 8 hydroxyquinoline vs 4 7 dimethoxy 1 10 phenantro lot of work and colorectal cancer 3 mcr of barbiturate neurogenesis in skeletal muscle total synthesis of iromycins synthesis of 2 methyltryptamine synthesis of 1 chloro 3 aminopyrazolylisoquinoline synthesis of 7 prenylindole juin 7 mai 7 avril 2 mars 2 février 6 group meetings chemistry course fukuyama group metting problems ccb challenging problems eavsn group seminar m t crimmins stoltz theses archive stoltz group clubs mechanism stoltz group clubs literature phil baran princeton organic chemistry supergroup dave macmillan