IBS started to build up the NC collection in 1984, and to-date it has grown to include over 68000 compounds. Originally the main contributors of natural compounds & derivatives were research institutes of the former Soviet Union, e.g. institutes for plant chemistry, bioorganic chemistry, botanical institutes, institutes for biochemistry of microorganisms, phytopathology of plants etc. With time, we have expanded our sources of rare and unique natural compounds and over the past decade the collection has considerably grown due to the influx of natural products from Asia, Latin America, some European centers for natural products etc. In percentage terms, the collection can be said to comprise 30 – 35% of strictly natural compounds isolated from plants, microorganisms, marine species etc.; approximately 40% are derivatives of natural compounds, i.e. modified alkaloids, terpenoids, flavonoids etc, and the remaining 25-30% are mimetics (analogs) of the strictly natural compounds, e.g. azosteroids, azocoumarins, conjugated isoindole systems, oxaterpenoids etc.

Of the whole NC library, 60 – 65% are compounds of plant origin; 5-10% were isolated from microorganisms, about 5% from marine species and the rest from other natural sources. All compounds have purity at 92-98%. The structures and stereochemistry are confirmed by various physicochemical analytical methods, including NMR (Brucker 300 – 500 MHz), mass spectroscopy and in some cases X-ray analysis.

The most representative classes include various types of alkaloids (several thousand compounds), terpenoids (several thousand), flavonoids and coumarins (over 3 000 compounds), peptides, glycosides and nucleosides (over 1 000 compounds), phenol compounds (several hundred). The collection is also rich in rare and unusual compounds, such as various classes of phytoalexins, allelopathic agents, specific sex attractants, natural toxins, unusual sesquiterpenoids and other secondary metabolites. Apart from this, we also have a collection of functionalized natural compounds which can be used in Natural Combinatorial Chemistry as natural matrices. Compounds in this collection are available in the amounts from several grams up to several hundred grams. As a rule, we package natural compounds in vials or microplates as 2 mg – 5 mg – 10 mg – 20 mg – 50 mg samples.