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Articles tagged with: epoxidation

Still In The RBF »

[29 Aug 2010 | 33 Comments | 25,297 views]
Solandelactone E

Aggarwal, Robinson. ACIEE, 2010, EarlyView. DOI: 10.1002/anie.201003236

A question – how long does one spin-out natural products based on one particular method?  I ask this as this is the second synthesis I’ve written about this year by Aggarwal, both using his lithiation–borylation–allylation sequence (the first one was in Chemistry World in June).  Aggarwal’s work is still very fresh – that’s why it’s on it’s second appearance here – but other groups have been stuck in a methodological rut for sometime (not wanting to name names here, but this is …

Still In The RBF »

[18 Aug 2010 | 17 Comments | 22,285 views]
Manzamine A

Fukuyama, Toma, Kita. JACS, 2010, ASAP. DOI: 10.1021/ja103721s
Ah – now this is a bit of a blast-from-the-past.  I knew I’d written something about this molecule before, so I had a quick rummage in the Tot. Syn. folder on my PC – and found nothing.  So I had a look in the other Tot. Syn folder, and another place I keep stuff for this website, and then four or five other places… (yeah, great filing system here) …and it turned up in this presentation I wrote a life-time ago.  You can …

Still In The RBF »

[11 Jul 2010 | 14 Comments | 14,887 views]
Urechitol A

Watanabe, Sumiya, Ishigami. ACIEE, 2010, EarlyView. DOI: 10.1002/anie.201002505. [No SI available]
As much as biological activity is a great rationale for working on a molecule, I do like it when a group does the chemistry for the chemistry.  To quote Watanabe, ‘Although urechitol A itself exhibited no biological activity, its unique tetracyclic structure prompted us to investigate its synthesis‘.  And when a group can make such an interesting molecule without too much resource, why not?  Key, of course, was building that fascinating cycloheptane, featuring not one, but two oxa-bridges.  Their plan was to …

Still In The RBF »

[16 Mar 2010 | 13 Comments | 14,024 views]
Coralloidolides A, B, C, and E

Trauner, Kimbrough, Roethle, Mayer. ACIEE, 2010, EarlyView. DOI: 10.1002/anie.200906126.
It’s not often I get to summarise an entire paper in one scheme, so I’m not.  Erm, what I mean to say is that I could, but I think for decencies-sake, I’m going to pad this out a bit!  Back in 2006, Dirk Trauner (still at Berkeley back then) completed a rather neat synthesis of Bipinnatin, completing the target in a rather neat nine steps (including a very nice Alder-ene reaction…).  This synthesis was actually a means to …

Still In The RBF »

[18 Jan 2010 | 16 Comments | 16,286 views]
Hyperforin

Shibasaki, Kanai, Shimizu, Shi, Usuda. ACIEE, 2010, EarlyView. DOI: 10.1002/anie.200906678. ; Shibasaki, Kanai, Kuramochi, Usuda. Org. Lett., 2004, 6, 4387. DOI: 10.1021/ol048018s. 
Three amazingly tough targets completed in (almost) as many months – you can’t tell me that total synthesis is stifled.  Hyperforin has been staining the white-boards of many a lab for decades – the isolation (reported in Antibiotik…) was way back in ’71, and has resisted synthesis until now.  Shibasaki himself has been working on it for quite a while, as you’ll have seen in the header – a key …

Still In The RBF »

[10 Jan 2010 | 17 Comments | 14,084 views]
Isatisine A

Kerr, Karadeolian. ACIEE, 2010, EarlyView. DOI: 10.1002/anie.200906632.
It’s always going to be a tough situation for the article I blog following something like Palau’amine, but this short and sweet synthesis by Michael Kerr of the University of Western Ontario (in the other London – which I visited in ’95) is as good as can be.  The rationale for it’s investigation is also pertinant, as it turns out that Isatisine A is a moderately active HIV isolate (EC50 of 38 ?m).  A secondary interest in the isolation was …

Still In The RBF »

[15 Dec 2009 | 16 Comments | 13,079 views]
1-Deoxynojirimycin and 1-Deoxyaltronojirimycin

Davies, Bagal, Lee, Roberts, Russell, Scott, Thomson. Org. Lett., 2009, ASAP. DOI: 10.1021/ol902533b.
More of a post-ette than a full post, this tasty little nugget was found buried amongst effective reposts and updates.  Out there to give you a freaky sense of de ja vous are full papers on kendomycin, spirastrellolide, nakiterpiosin… finding something new was an effort!
What we’ve got here are a pair of closely related synthese of some poly hydroxylated piperidenes; notable for their glycosidase inhibitory effects.  Huh, I hear you say (actually, probably not – there are …

Still In The RBF »

[17 Oct 2009 | 57 Comments | 22,284 views]
Platensimycin

Njarðarson , McGrath, Bartlett, Sittihan. ACIEE, 2009, EarlyView. DOI: 10.1002/anie.200903347.
It’s back!  Twice in as many weeks, too, as KC has decided to drop the details on his many syntheses of platensimycin and platensin into a full JACS paper.  However, I’ve spent enough time looking at his work in this area, so it’s a pleasure to examine this synthesis by Jon Njarðarson of Cornell.  I should point out that I don’t feel that this is necessarily the best route, but it’s got some damn smart chemistry in it, so what …

Methods, Still In The RBF »

[25 Feb 2009 | 14 Comments | 14,906 views]
BE-43472B

Nicolaou, Lim, Becker. ACIEE, 2009, EarlyView. DOI: 10.1002/anie.200900058.
Huh; you wait months for a Nicolaou synthesis, and then two come at once!  This little beastie and sporolide B dropped in Angewandte on consecutive days, both represented by abstracts drawn in the now familiar crayon-o-vision styling of La Jolla’s most-prolific chemist and photoshop abuser. Seriously, check this stuff out – this is on his home page!  The last time I saw anything like this I’d been over-doing both the ether and the geocities…

Of course, all this wouldn’t be …