Heliotropyl acetone

Heliotropyl acetone

Not to be confused with: heliotropyl acetate.

White crystals.

Easily soluble in ethyl alcohol @10%.

Mild smelling, sweet, fruity, long-lasting raspberry-like odour.
I was expecting some resemblance  with heliotropine (sweet, powdery floralcy), but this one has a quite different odour profile.

It has very much in common with raspberry ketone: it possesses a jammy, red fruit-like character. Somewhat dry and woody, not much powdery. Rose ketone nuance.

It shuold be interesting in jasmine imitation bases. As suggested by S. Arctander for raspberry ketone, I think that Dulcinyl would also fit very well in a synthetic jasmine composition, bringing a realistic and elegant fruity juiciness very characteristic of some absolutes.
In his work he reports some resemblance with “the sweet-floral notes in Mimosa and Cassie“. Interesting to note that this product is called “Cassione” by Firmenich.

Colourless crystals.

Not ready soluble in ethanol (@2,5% only) or DPG (it forms a cloudy solution).

Floral, warm animalic (civetty), sweet honeyed, thickpowdery, sharp, slightly urinic smell.

Superior to any other p-Cresyl derivative in my opinion. Rounder and much floral than p-cresyl acetate (“horsey” notes) or p-cresol (jasmine-like): it bears a closer resemblance to narcisse, jasmin and violet. Also sweeter, higher-boiling (greater tenacity) and more delicate than the former.

It can easily mimic the violet with the sole addition of indole and ionones. The same for narcisse, being careful in replacing the ionones with methyl anthranilates and a hint of greeness. On paper and diluted, it is almost like smelling a dried out strip of jasmine absolute.

Interesting in a rose-jasmin complex: a warm animalic side married with a powdery phenylacetic acid (dirty honeyed) suggestion.
A short digression on an old perfume: JOY, Jean Patou. Warm and powdery, slightly harsh, intensely floral and jasmin, quite linear. I bet this molecule along with phenylacetic acid was used there (and a lot of Musk Ketone, rose and jasmin absolute, of course).

In jasmine reconstitution I would prefer p-cresol over p-cresyl acetate: it is sweeter and floral; in narcisse and tonkin musk imitation p-Cresyl acetate is my choice; while p-Cresyl phenylacetate elegantly and quite discreetly (in low dosage) fits in both (slightly too much floral for a musk accord, but nice in civet).

Definitely the richest, most floral, animalic, lively, nuanced and smooth p-cresyl derivative out of the three (I didn’t mentioned here p-cresyl methyl ether since it is the most different: thin, low-boiling and ylang-like).

Surely one of my favourite “floral” chemicals, along with indole, linalool and methyl anthranilate.

Molecular structure reference: S. Arctander works. Image created using ChemSketch.

Molecular structure reference: S. Arctander work. Image created using ChemSketch.

White flakes.

Warm, honeyed, metallic, sweaty odour, resembling rose with an animalic (castoreum) and jasmine-like nuance. Dry, medicinal, sweeter on dilution.

In traces it could lend interesting effects in jasmin, rose, cuir type fragrances, tobacco or animal accords.

This product doesn’t resemble civet on its own (in my opinion) but, as suggested in some works, I understand its use in civet imitation bases. Somehow dirty (not fecal): it is waxy, fatty, sweet and slightly acrid (tanned leather, vinegar, feet-like odour) and it could bring texture and roundness to the stronger skatole or indole.

What is surprising about this material is that it lasts forever on paper or tissue. According to S. Arctander’s Perfume and Flavor Chemicals, phenylacetic acid is

[...] one of the most tenacious odorants of all known and used perfumery materials. It will outlast Vanillin on a ‘blotter test’ and a 5% solution of Phenylacetic acid may last more than 3 years on a blotter [...]

Text printed on graph paper. The blurred effect was obtained with an alcoholic solution of phenylacetic acid and a tracing paper. Surely, you can't smell it, but the odour really adds something to it.

Text printed on graph paper. The blurred effect was obtained with alcohol and a tracing paper.

An old De Laire base (much probably reformulated today).

This base was created in the 20′s (1915-1926?) by the French company De Laire. In the 1939 de Laire’s ‘Notice des produits pour la parfumerie’ (a perfumery products catalog for their customers) the Amber 83 is described as follows:

“Produit de choix pour les notes orientales et parfums ambrés très aimés aujourd’hui.

Sa finesse, alliée à beaucoup de puissance et de ténacité, explique aisément le succès qu’il a rencontré dans des genres très différents d’emplois, en France comme à l’Etranger.
[...]
Son point de ramollissement assez bas nous permet cependant de le mouler en petits morceaux d’égales dimensions, et de couleur relativement claire [...]“

Translation: “The best product for oriental notes and ambery perfumes, very much enjoyed today.

Its subtlety, combined with much power and tenacity, easily explains the success it has achieved in many and very different uses, in France and abroad.
[...]
Nevertheless, its quite low softening point allows us moulding in small pieces of the same size, quite light in colour [...]

It is interesting to notice how the original amber was sold in a solid form, pale in colour.
This may suggest that much of the formula were nitromusks, vanillin and maybe resinoids (like benzoin).

The sample I have is physically different.

Appearance: pale yellow, pourable liquid (DPG’s like viscosity). May form a crystallin precipitate in the cold. This is sort of a diluted version of the original base that I suppose was a yellowish solid.

This is the archetypal “amber” of perfumery. Nothing in common with the ambergris, the sperm whale secretion.
This one is based on vanillin or similar products (a heavy dose), powdery musks, some patchouli (but not earthy and terpy), sandalwoodbalms (Tolu) and resins (labdanum, benzoin and styrax), plus a rosey, geranic note in the heart. Nutmeg and maybe cardamom lend some spiciness.
Everything is wrapped and smoothed out by the vanillin overdose. I also detect a civetty facet.
Long lasting and musky, powdery, vanilla absolute-like in the drydown, The sharp, incensey labdanum signature is still alive till the very end, discreetly.

A masterwork of balance, good structure, fine details, simplicity. Easy to recognize.

As almost any bases do, it needs incorporating into a fragrance, to give some boost and projection, especially in the very beginning. The high vanilla-musk dose is something that won’t come out easily, laying down close to the skin.

Here is a (solid) amber type formula from a 1931 book (Le livre du parfumeur – Félix Cola, chimiste-parfumeur), to give us an idea of the composition of such bases:

AMBRE SYNTHETIQUE N°3      
 
Musk Kétone     425 grammes
Muscambrette     100
Héliotropine     75
Vanilline       225
Résinoïde de Benjoin   100
Baume de Tolu     75
Ambréine absolue     50
Résinoïde d’encens     50
Vétyvert Bourbon     10
Patchouly     10
Acétylisoeugénol     110
Stéarine       170
        1400 grammes

Musk ambrette is now forbidden, but could be replaced by the flowery-type musk: ambrettolide, galaxolide or Romandolide (not powdery, but more ‘vegetal’ and clean in comparison to ancient musks, Romandolide in particular).
The ‘ambréine absolue’ is sort of a purified labdanum.
I don’t really know why stearin appears in the formula.

The composition in this photo was inspired by the Ambre 83 base. You can notice Tonka seeds, vanilla pods and geranium leafs. Photo: perfumechemicals.com

The still life in this photo was inspired by the Ambre 83 base. You can notice Tonka seeds, vanilla pods and geranium leafs. Photo: perfumechemicals.com

Pale yellow, ambery mobile liquid (denser than the redistilled quality).

Soft, sweetsawdust-like, patchouliy odour. Drier and more powdery than the redistilled one. Almost no trace of terpenic, mouldy, “cooked vegetable” notes.

In the opening it starts very softly, it has a very poor impact (if kept in cold you barely could tell you are smelling patchouli at all). Then, it opens up and blooms in a beautiful, well refined, cedary, dusty, camphory, clean patchouli. Fruity plum-like nuances. It’s less green-floral than the redistilled quality, but woodier. It does smell a little earthy, but in a clean way: without any mouldy effect.

I like to think this smells like a summery walk in the woods by night: you can detect dead leafs, wet wood and an earthy odour, while a cold humidity arising from the dark chills you to the bones. It also recalls me the smell of rain.

Modern (linear) and interesting. It is well-faceted and complex. I think it is special and different from a simply redistilled oil because here’s the intelligence of some mind that picked-up some fractions and put them together shaping a new character, different from any other patchouli oil.

I can also perceive an ambery (ambrox-like) captivating facet: woody, dry, musky and addicting. Do I detect an animal whiff? Maybe, or simply this oil recalls me some 70′s 80′s animalic bases (like the Animalis, Synarome) used not infrequently in those years in perfumes like Yatagan (Caron, 1976), Antaeus (Chanel, 1981) or Kouros (YSL, 1981): a patchouli-cedar theme, enriched by costus root castoreum and civetty notes, completed by fatty, incensey aldehydes (c12 MNA-like).

Long lasting and beautiful in the dry down. Dry and cedary, ambroxy, orris-like.

A 3D (sort of) gif I made. Photos taken in the woods near Versailles.

A 3D (sort of) gif. Photos were taken in the woods near Versailles.

Pale yellow, mobile liquid.

A very fine, smooth, silky patchouli oil. The terpy, mushroomy, earthy notes: erased in this redistilled quality.
It starts a little softer than the regular one: there’s only some distant green, leafy suggestion. It is velvety and rich in the heart. It dries out in a cedary, woody, dusty, ambery very patchouliy odour. It is indeed very long lasting.
I can smell some resemblance to narcisse absolute: its vegetable greenness, soft floralness (powdery and pollen-like) does suggest me an interesting and unexpected facet. Somehow hedione-like.

This is an intermediate quality between a regularly distilled oil and a fractioned one. Here the bouquet is lighter than the regular but finer. It is quite similar to the fractioned patchouli oil (see: Patchouli Coeur n.3 – IFF).

Very modern and linear. The most useful quality in my opinion: not too much chaotic or dirty in the top notes, ambery and velvety, elegant and simple all throughout the evaporation.

The IFF logo and name are a trademarks of IFF.

Green, fatty (aldehydic), acidic, rose ketone-like. Refreshing and juicy, really like biting an apple. Powdery and woody (similar to a patchouli coeur, Piconia or Verdox). Hints of floral fruitness. Well rounded and balanced throughout the evaporation. Maybe a little soapy, detergent-like (is my judgement somehow biased by my experience with functional products, that often contain such appley accords?). Quite a ‘perfumey’ apple, indeed.

On drying out the odour become more fruity, still dry and fatty, very apple-peel like. Hints of green, rose, geranium. Bright and sweet. Iris-powdery. On further evolution I can get whiffs of cinnamic alcohol-like molecules, sweet spicy, fruity and waxy, woody and very damascone or aldehyde C14-like.

Personally a very beautiful base, intelligently and technically well done. I like the many facets that refine the composition: the nice green accord and the beautiful waxy fatness. Moreover, it preserves its identity and character till the end.
Very much like the real thing, juicy and fleshy, astringent. Well balanced at any moment and nicely rounded, one can almost taste the peel and the flesh. As I said, a little bit ‘perfumey’… too sweet, not waxy and fatty enough at some point in the dry down.

But comparing a base to the object it mimics is often not satisfying. Considerations have to be made on the intended application: has been this base mostly conceived for functional products (a choice imposed by trends in perfumery)? Furthermore, would a copycat of nature be interesting enough on a technical point of view, would it stand itself like this base mostly unchanged and still alive for more than 12 hours?

My answer to the last question is simply: No. Not to talk about regulatory issues… nature actually has a much wider palette than a perfumer.
Concerning its use in fine fragrances: I think it would be good as well, since this base has many interesting facets that would come out even better in an hydroalcoholic menstruum, and possibly open smoothly on skin.

Pale yellow, mobile liquid.

Very fine and fresh, soft floral, with hesperidic nuances, well rounded. Slightly pungent, vert, terpy; evoluting from white fresh flowers to a metallic, rosey, ocimene-like, warm odour; very slightly indolic, but in a pleasant way, perfectly balanced.
A subtle, sweet tension produced by some linalyl acetate-like molecules, enlightens its aura. It somewhat recalls me the odour of wet, hot cotton tissue. It has a powdery, ‘clean’ aspect. After 15 minutes smelling it beautifully dries out and stabilises in a pronounced hesperidic bergamot-petitgrain-like whiff, and a tender flower suggesting hints of hay, tobacco, civet under a green fleshy and waxy veil.

Smelling this oil, discovering its facets throughout the evaporation curve is enchanting, a charming experience.

I like to ask me how one could use this product in a new, original way. Besides conventional compositions (colognes, chypres, fougères) or soliflores featuring orange blossom or rose, this material may need complete reinventing. It does smell just wonderful all alone, simply diluted in alcohol. It’s great in simple mixes (with woody, musky materials), but quite boring.. I think I should do some research on the flowery side of the perfumer’s palette. For example: it could be worth testing in some fine Narcisse, Lilac base, or leafy, green, imitation tea accord (its sweet fruitiness does fit well, indeed).

Mild smelling butyric, iso-valerate-like odour. It should be classified as fruity and classical plum-like. It exhibits a certain fresh sweeteness similar to some linalyl esters, but here a distinctive woody, dry, tobacco-y facet dominates the overall aspect. 

There might also be a rosey, green-metallic nuance. It is quite persistant, an heart note I would say.

Very nice in fruity accords: together with iso-amyl iso-valerate, bergamot eo or bergamot smelling chemicals (ethyl linalyl acetate), cassis absolute (or labienoxime 10%, cassyrane or other foxy, cat urine-smelling chemicals) and aldehyde c18/c14, it forms a sweet peachy bouquet.

In a fancy tobacco accord (preferably with tobacco absolute) it may constitute the plum-like note distinctive of some aromatised blends (plum juice concentrate).

Here’s a simple ambroxy/woody/burnt tobacco accord you can try with/without Datilat:

TOBACCO ABS
MOUSSE DE CHENE IFRA (with patchouli and ambroxid to form an easy and pleasant accord)
BENZYL SALICYLATE
ETHYL VANILLIN
COUMARIN/BICYCLONONALACTONE
BIRCH TAR (trace)
HEDIONE (for diluting and mellowing effects)
CIVET ABS (recalling some strong tobaccos)
AMBROXID (to make the all thing wearable)
PATCHOULI COEUR (I usually don’t like messy top-notes, this one I prefer)
COSMONE (nice velvety effect)
GUAIACWOOD EO
CLOVE (as a modifier)
+DATILAT and/or ISOAMYL ISOVALERATE (if using iso-amyl iso-valerate be sure to add some top-notes like mandarin or bergamot in order to round its effect. It is quite volatile and it could unbalance the accord)

In this first attempt I tried to extract the aromatic principles of roughly 0,5 kg Bourbon vanilla beans (from Madagascar) by hydrocarbon percolation. For this purpose I used n-hexane Scharlau 95% (120 euros 5 L canister). The extraction product is called an “oleoresin” (resinoid or concrète) because it carries a volatile fraction and odorless waxes and resins (I suggest you to read S. Arctander’s monograph on this subject: Vanilla oleoresin).

I bought extraction grade vanilla beans: water content is kept low.

I was quite satisfied with the overall “standard” odor quality of the starting material: “senza infamia e senza lode” (nor too bad nor too good). I only perceived a faint fermented type, volatile off-note when unpacking the beans. Apparently it was distilled off when evaporating the solvent, since it is not detectable in the oleoresin anymore (when disassembling the Soxhlet extractor after the process I was able to smell an acetic acid-like note on the top of the Dimroth condenser, while the recovered hexane did not carry such note).

In this first photo you can see the Soxhlet type apparatus I’ve set up for the extraction process:

Soxhlet apparatus

Soxhlet apparatus

Here’s a video of the soxhlet extraction process:


Comminuted Bourbon vanilla beans before extraction:

comminuted vanilla beans

comminuted vanilla beans

Comparison between exhausted (left) and fresh (right) vanilla beans. From this photo you can guess the extractive power of hexane: the vanilla on the left is drier and paler in color. It still carries some aromatic principles (not hydrocarbon-soluble material I presume).

exhausted (left) fresh comminuted vanilla beans (right)

exhausted (left) fresh (right) comminuted vanilla beans

A Soxhlet apparatus is designed in order to recirculate the solvent throughout the botanical material. The temperature at which the extract is exposed is the boiling temp. of the solvent used. At standard pressure n-hexane boils at 68° C (relatively low). The raw material is not directly in contact with the boiling solvent, thus preserving it a little bit from excessive heating.

In this first attempt I let the solvent recirculate 6 times (2 hours refluxing). The first run is, not surprisingly, the most charged with volatile materials, waxes and pigments (it is the darkest in color). The fourth is almost colorless.

I let the extraction liquor stand for a day and then filtered under gentle vacuum. This process results in a small loss of solvent. n-hexane is very volatile and vapors arise easily from the filter paper. It is the most troublesome phase of the process, when you are in strict contact with the solvent. I carried out this operation on the outside avoiding breathing too much vapors.

vacuum filtration

vacuum filtration

I then evaporated the solvent under vacuum (pressure between 150-300 millibar) at ~30° C. It is really tricky to evaporate all the solvent. The last traces are the most difficult to eliminate: the temperature increases and there is the risk of spoiling the extract.

recovered solvent (left) vanilla oleoresin (right)

recovered solvent (left) vanilla oleoresin (right)

A video I recorded of the evaporation process:


A rotatory evaporator would give better results: solvent recovery would be faster and more efficient.

I used a water vacuum pump: I can reach a pressure as low as 8 millibar, but in normal working conditions (heat, arising vapors) it is stable at around 150-200 millibar. A membrane pump would be more reliable.

An ice trap would also improve solvent recovery and avoid vapor leakage in the air (I used a Dimroth condenser and recovery was very good, I registered only minor losses through the vacuum pump).

The yield was quite good: 31 g oleoresin from 471 g of crude vanilla beans (6.7%). I was able to recover most of the solvent (major losses were due to filtration and adhering solvent on exhausted vanilla).

Vanilla oleoresin is a viscous, dark brown liquid not completely alcohol-soluble. It possesses a true-to-nature, rich and creamy vanilla aroma, with woody and licorice undertones and a tobacco nuance. It is not as powerful as a vanilla absolute, since it still contains odorless waxes and non-volatile material, but it possesses good tenacity.

I don’t appreciate headnotes from this oleoresin very much: they are quite smoky-bitter, overly sweet to my nose. It may be a factor of concentration (too high to fully appreciate the extract) or there could be solvent traces (a gassy nuance? Not quite sure). I assume that during solvent recovery the temperature increased too much in the last minutes (bitter, smoky, burnt odor detected?).

An hydrocarbon extraction followed by an hydro-alcoholic one should give better results: not complete alcohol solubility, but a much more complex and rich aroma quality.

Tightly controlling the temperature is essential to achieve satisfactory odor quality.

Not sure if it is a panteted molecule (IFF).

It is piercing, woody, resinous, musty and rosy in some ways. It is peculiar and interesting, not sure to have smelled anything that resembles this until now. Not at all ozonic (like Floralozone or Precyclemone B) nor marine, as stated in some descriptions; it has no lily of the valley-melon-like nuance. A little bit salty, maybe.
It is the odour you could find in a cellar, quite thin and volatile. This has not much body but is quite long-lasting. I very much appreciate its extremely dry, woody, musty, cork-like undertones.
It is quite powerful, difficult to use at more than 5%.

Sweet, tonka, almond-like, dry, woody odour. Lactonic nuance.

Its strength is better understood when properly diluted (usually at 5 or better 1%, in ethyl alcohol; anyway it will not dissolve at more than 8%). I usually keep it at a maximum concentration of 1% (fragrance concentrate), otherwise, it will grow and tend to overwhelm other notes.

It is a standard ingredient in chypres and fougères. It forms the classic ambrein accord together with vanillin, civet-like notes and bergamot.

Tonka bean absolute is quite obviously more complex and refined, it has soft, woodier, bitter, creamy, hay-tobacco-like, dark facets.

I have not yet found a good replacer for coumarin at this time. It could be Acetanisole (but it is thinner, sweeter, heliotropine-like in character). I really like Bicyclononalactone (closer to tonka, hay and hyraceum).

Powerful, thin, sweet, fresh, lavender-like, fruity, metallic, citrusy (linalyl acetate-like), clary sage-like, well recognizable odour.

Used in almost any manly fragrance, classic fougère accord, modern sweet-musky-chypré accord. From fine fragrances to functional products.

@ 100% intense, sweet, fruity, peary, green, ananas, oily, slightly waxy, fresh.

@ 10% pleasant, fresh, sweet, fruity, peary, metallic.

Used to introduce a modern fresh-fruity topnote. It blends well with iso e super and dihydromyrcenol in fougère accords.

Real nitromusk: warm, sweet, musky, dry, powdery, fruity, soft odour. Most polycyclic and macrocyclic musks lack that beautiful sweet-powdery undertone. Tends to discolor.
iso-Muscone and Velvione are examples of nitromusk-smelling non-nitromusks. They are safer than nitromusks but do not perfectly mimic that nuance.

Sandalmysore core
Santaliff

Medium-smelling, sweet, oily, slightly aromatic (dry fennel), sandalwood, musky, vibrant, woody odour. Effective in small amounts, it gives a natural milky, creamy, sandalwood-like nuance.

Powerful, sweet, milky, lactonic, coconut, coumarinic, powdery odour.
I used this in an imitation rum fragrance, where it surprisingly well mimics the effects of oak aged liquor: it provides a refined sweet, mellow, lactonic, woody, dry, musty nuance, and gives tenacity.

“Methyl Laitone 10% is one of the new “spiro”-lactones developed and patented by Givaudan. It is extremely powerful and very effective in all accords where a creamy, fruity volume is required. It provides “cosmetic” body to white flower notes such as jasmine, gardenia, tuberose and ylang ylang, and to fruity accords like peach and osmanthus. In sandalwood accords it provides milkiness. Coupling with coumarin and hay notes makes it extremely interesting and polyvalent. Its dry note is very noticeable, especially on humid and dry fabric.” (http://tinyurl.com/mlaitone10)

Medium smelling, sweet, powdery, milky, dry, typical vanilla odour, without any complexity, or dark shades. Useful in any composition. @ as little as .1%, whitout being perceptible as a single note it rounds off and mellows any fragrance.

gamma-Nonalactone

Intensely sweet, creamy and coconut-like odour. Oily, waxy and metallic undertones. Useful in many florals.
“Its intense sweetness and tenacity is often utilized along with that of Undecanolide (…) in Gardenia, Tuberose, Honeysuckle, Stephanotis, Plumeria, Jasmin and many other heavy floral types.” (Arctander)

gamma-Undecalactone

Medium-smelling, fruity, lactonic, peachy, sweet, oily, powdery. Effective in low concentrations, otherwise it tends to overwhelm other notes and give ‘opacity’. It may also be used in floral compositions, tuberose for instance.

Semisolid-viscous intensely yellow, blue fluorescent, mass.

Similar in odour to methyl anthranilate, but more sweet, oily, waxy, powdery and floral.
Useful for the same purposes as methyl anthranilate, where more tenacity and sweetness is desired. It is also more stable.

@ 100% pungent, chemical, thin sweet, heavy-flower, ylang, fruity, musty, grape.
@ 5% sweet, floral, ylang, orange blossom.

Useful in low concentrations in floral compositions, in imitation orange blossom, neroli, jasmine, tuberose, narcissus…
It reacts with aldehydes, forming condensation products (Schiff’s bases). Aurantiol is hydroxycitronellal+methyl anthranilate.

Very mild, almost non-smelling, nondescrpit, oily, sweet, floral odour. It tends to oxidize to benzaldehyde, which is strong-smelling and easily ruins its floral profile.
“Used in perfumery as a blender, in some florals quite extensively, Jasmin, Gardenia and Lilac may often be composed using Benzyl alcohol although this material is really dispensable in most cases.” (Arctander)

Quite powerful, similar to eugenol, but more fruity, floral, delicate, less woody-spicy. It strongly resembles carnation and it is usually found along with benzyl salicylate to form a classic accord.

Strong smelling, clove, spicy, woody odour. Bitter in too high concentrations, natural spicy, woody effects if properly diluted (usually @ around .1%). More refined, less woody, musty, green than natural clove oil.

Powerful, green, leafy, fresh, sweet, woody odour. It easily reminds of freshly crushed leaves, cut grass, green branches. In dilution it is more sweet and almost fruity. It gives a natural impact to fruity and floral compositions, imparting a realistic green effect.

Poweful, predominantly green, sweet, waxy, citrusy odour. Used in traces for an herbe coupée effect. It is less natural, more powerful than cis-3-hexenol, but it is more rounded and blends better with fruity-floral notes. 

Sweet, soft, pleasant, fresh, nondescript-flowery odour. It may resembles jasmine for its fruity-juiciness aspect. It is less refined, stronger than hexyl cinnamal. It is useful in any white-floral composition.

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