The Age Of Adaline Book Author
Niklas Terki
Coccinellid beetles contain a variety of defensive alkaloids that makes them unpleasant for various predators [1]. Over 50 alkaloids have been characterized from ladybirds until now, including perhydroazaphenalenes, aliphatic and aromatic amines, piperidines, pyrrolidines, azamacrolides, dimeric alkaloids and homotropanes [2]. The majority of these alkaloids have an endogenous origin. In a dangerous situation or predator attack, the beetles can emit droplets of hemolymph. This substance comes from the tibiofemoral joints situated in their legs, a mechanism known as reflex bleeding. This situation brings the alkaloids to the surface as an early warning signal to the attacker.
The fluid toxicity and bitterness, added to the characteristic odor of these insects, have been regarded as a protection against insect or vertebrate predators [3]. Bicyclic ring systems bearing a nitrogen bridge are often found in nature [4-6]. Typical examples include cocaine, atropine, and scopolamine. These compounds are 8-azabicyclo[3.2.1]octane derivatives and belong to a large class of natural products known as tropane alkaloids [7-9]. In contrast to tropane alkaloids, the higher homologs homotropanes (9-azabicyclononanes) are less common in nature, but not less important. They possess biological properties, such as nicotinic acetylcholine receptor (nAChR) ligand [10,11], CNS (central nervous system) activity [12,13], and chemical defense [14-16]. Structurally, homotropane alkaloids have different skeletons including [3.3.1], [4.2.1] and [3.2.2] (Figure 1).
Recent elegant studies by Steele et al. [38,39] provide an insight into the impact of pathogen infection upon production of the alkaloid 1 in A. bipunctata. When A. bipunctata was infected by the microsporidian pathogen Nosema adaliae, larval development was significantly delayed. At elevated temperatures, developmental delays caused by infection were reduced, spore counts and infection decreased, and there was an increase in the content of 1 [38]. In a second study, the authors evaluated the effects of the N. adaliae infection and food availability on production of 1 [39]. Infected A. bipunctata were shown to produce more 1 than uninfected adults. Furthermore, the daily fed adults produced more of 1 than those adults that were fed irregularly, and uninfected adults that fed irregularly had the lowest content of 1. The infection load of adults was significantly increased in beetles that were fed irregularly. Taken together, these results suggest that 1 may provide A. bipunctata with chemical defence against pathogen challenge.
As previously reported by King and Meinwald [29], synthetic strategies have been designed and employed in the synthesis of adaline (1) and euphococcinine (2), before 1995. In brief, 1 and 2 were synthesized in both racemic and asymmetric forms. Key (homotropane construction) steps included: i) inter and intramolecular Mannich reaction; ii) double Michael addition in the cyclooctadienone derivative; and iii) intramolecular 1,3-dipolar cycloaddition. As shown in Scheme 1, the azabicyclononane ring is an interesting target for strategies based on the Mannich reaction. This methodology is mostly used in some cases, with few steps, and from commercially available reagents.
The peculiar structural factors of homotropane alkaloids added to the intriguing biological activity exerted by ladybirds (as demonstrated in this review for A. bipunctata), besides the fact that the insect releases these substances in minimal quantities, make these targets highly relevant when considering total synthesis. Since Tursch's pioneering work, several total and formal syntheses of homotropane alkaloids released by coccinellids have been carried out, contributing to a more accurate chemical and biological understanding of these alkaloids. Specifically, in this review, the main points in the synthesis of coccinellid alkaloids are: i) dipolar cycloaddition; ii) olefin metathesis; iii) intramolecular Mannich reaction. Cyclization steps, summarized in Table 1, have shown to be efficient in the construction of an azabicyclononane system and also to provide enantiomerically pure alkaloids.
Therefore, homotropane-based compounds continue to attract the attention of researchers involved in the progress for new synthetic methodologies to reproduce these natural products and synthesize their analogs, improving existing methods.
2021 Lima et al.; licensee Beilstein-Institut.
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I set out to read Amelia Opie's novel Adeline Mowbray more from sociological than literary interest: an 1804 treatment of voluntary cohabitation outside marriage couldn't fail to grab my interest, especially since this is a topic treated surprisingly seldom even by modern authors. Opie was, then, politically ahead of her time, but she surprised me by also writing an engaging book, if one at times infuriating to a contemporary sensibility. Despite some standard-issue melodrama and creaky plot devices of the type often found in eighteenth-century "novels of sensibility," the pages flew by whenever I picked up Adeline Mowbray, and the author's sneakily satirical wit kept me guessing to some extent about exactly who she was condemning and for what cause. (I also couldn't avoid a gossipy curiosity about how the novel's models, Mary Wollstonecraft and William Godwin, took to their friend Amelia's representations of them.) Of course, my level of engagement was increased by the fact that I was constantly arguing with Opie, which I believe to be exactly the reader response she intended. Even if she was not speaking to the gender politics of twenty-first century America, she was undoubtedly writing to provoke, and it's pretty remarkable that she still manages so well after two hundred years, albeit not exactly in the ways she might have foreseen.
To contrast with all these dire circumstances, Opie refuses to present the original objections that motivate her character Glenmurray (or motivated her friend William Godwin) to write against the marriage institution in the first place1. I found this a bit frustrating, as if I were listening to one side of a violent telephone conversation. But the reason for Opie's omission is built right into her text: ideas like those of Glenmurray were believed dangerous, irresponsible even to discuss lest some idealistic young woman like Adeline pick up one's novel and be led astray.
I mention "the wisdom of the ages" above, and indeed the idea is a real touchstone for Opie; the phrase is repeated some eight or nine times throughout the novel as different characters, and eventually Adeline herself, bemoan her foolishness in attempting to fly in the face of convention. Which brings up the whole question of progressiveness versus conservatism in different eras. To this modern reader, Opie's reluctance to even consider the possibility of challenging the status quo, merely on the argument that many previous generations have accepted it, seems strikingly conservative. Still, as Nymeth pointed out in a recent post on Wilkie Collins, a more nuanced view is necessary: in 1804, the mere act of writing a novel in which a sympathetic heroine decided to live with a lover outside marriage was a radical act. Although Adeline is punished (and punished, and punished some more) for her non-conformity, Opie never makes her the villain, and she more or less respects Adeline's ability to make a rational decision herself, rather than making her the victim of a scheming rake. What's more, although she chides Adeline for giving in to her youthful exuberance rather than respecting the wisdom of her elders, such an attitude is not gender-based; she takes the same line with Glenmurray, who published his offensive tract at the young age of nineteen. In some ways, then, Opie is quite subversive: she presents an intelligent, sympathetic woman who makes a hasty decision for all the right reasons, with a minimum of condemnation.
The presence of "an intelligent, sympathetic woman who makes a hasty decision for all the right reasons, with a minimum of condemnation" was the main reason why I so enjoy Aurora Floyd by Mary Elizabeth Braddon, and it sounds like the novels have a thing or two in common. I love novels like this, even though very often I get frustrated that they don't take their point just a little bit further. And I hadn't heard of this one until you mentioned it the other day, so thank you!
Having rejected marriage in my own life for pretty much the same reasons as you, I find this theme fascinating. I was thinking about two novels I read this year in which the heroines struggle with the decision to marry or to reject marriage: Gissing's The Odd Women and Sayers' Gaudy Night. Without giving too much away, I can say that both authors were sceptical of the feasibility of doing away with marriage, and though this goes against my instincts, in the end I understood where they were coming from. They both lived in time periods where there was a lot more at stake for a woman who didn't marry than there was for a man; where what each gender had to face in terms of social repercussions wasn't even comparable. And as such, the whole thing was simply not a fair deal. I'm incredibly grateful to live in a time and place where this needs not be a concern for me.
One thing that interests me is Adeline's decision to continue with her, shall we say, "social experiment" once she's begun to regret it. Assuming that happens while Glenmurray is still alive, is there ever any question of the two of them making it official? Does Adeline not have second thoughts until later, is she too proud/dedicated/idealistic/etc to change her mind? Or is it in any way his decision?