What is Iso E Super? The four molecules behind 5th Avenue's dry-downWhat is Iso E Super? The four molecules behind 5th Avenue's dry-down

On the 5th Avenue note pyramid, the base holds no familiar woods or resins. It holds four synthetic molecules instead. In niche perfumery these are chosen for the way they behave on skin, not as a cheap stand-in for natural materials.

Iso E Super

A woody aroma molecule developed by IFF in the 1970s. Smooth and dry, with a hint of cedar and amber. It rarely stands out as a clear note; instead it adds warmth and depth around everything else. Some people smell it strongly; others barely notice it on their own skin while the person next to them does.

Cetalox

Firmenich's trade name for a molecule from the ambrox family, modelled on ambergris. Mineral, slightly salty, warm like skin after sun. Cetalox makes the dry-down last and carry softly without weight.

Ambrettolide and Helvetolide

Two synthetic musks. Ambrettolide occurs in nature in ambrette seed: soft, slightly sweet. Firmenich's Helvetolide has a fruity, pear-like edge that links back to the pear and apple at the top of 5th Avenue. Together they make a clean, smooth base that smells like skin itself.

What a skin scent means

A skin scent stays close to the body and projects a short distance. These four molecules make 5th Avenue shift a little from person to person: body heat and skin moisture change each wear. The best way to know how it sits on you is to try it, not to read about it.

• Spray on the wrists or the back of the neck, and don't rub.
• Wait 15–20 minutes for the top notes to settle before you judge.
• If it seems to fade, your nose has usually got used to it; the scent is still there.

22:00 · Woody-Amber5th AvenueDressed for the avenue, undone after dark.View product