SK278018B6 - £(5-methoxy-4-oxo-4h-pyran-2-yl) methyl| carbanylates and method of their preparation - Google Patents

Abstract

£(5-Methoxy-4-oxo-4H-pyran-2yl)methyl| carbanylates with with general formula I, where is hydrogen or octyloxy group, are prepared so, that 2-hydroxymethyl-5-methoxy-4H-pyran-4-on is influenced with belonging phenyl isocyanates with general formula II in of anhydrous xylene environment at boiling point of reactive mixture during 5 to 26 hours. These carbanilates are usable in agricultural and medicine.

Description

Technical field

The invention relates to [(5-methoxy-4-oxo-4H-pyran-2'-yl) methyl] carbanilate and to a process for the preparation thereof.

BACKGROUND OF THE INVENTION

On the basis of the literature search as well as the patent literature, the substances listed under the general formula I are original, not yet described in the literature. They are derivatives of 2-hydroxymethyl-5-methoxy-4H-pyran-4-one, known as methoxytic acid, which exhibits antibacterial, antifungal, anti-inflammatory, insecticidal and pesticidal activity. Its use in cosmetics is known.

SUMMARY OF THE INVENTION

The present invention provides [(5-methoxy-4-oxo-4H-pyran-2-yl) methyl] carbanilalates of formula I wherein R is H, octyloxy.

The present invention further provides a process for the preparation of compounds of formula (I), which comprises treating 2-hydroxymethyl-5-methoxy-4H-pyran-4-one dissolved in anhydrous xylene with freshly distilled, corresponding phenylisocyanates of formula Π o-c-V

wherein R is as defined above, at the boiling point of the reaction mixture. The reaction time ranges from 5 to 26 hours. Equivalent molar amounts as well as a two molar excess of phenylisocyanate relative to 1 mole of methoxycanoic acid are employed.

The process for the preparation of the compounds according to the invention has the advantage that the reaction is carried out in a simple and easy manner in a molar ratio of methoxycanoic acid: phenyl isocyanate (1: 1 to 2), producing good purity products and in good yields.

EXAMPLES [(5-Methoxy-4-oxo-4H-pyran-2-yl) methyl] cabanilate 6.8 g (0.044 mol) of 2-hydroxymethyl-5-methoxy-4H-pyran-4-one are dissolved in 100 ml of anhydrous xylene and 10.48 g (0.088 mol) of freshly distilled phenyl isocyanate are added. The reaction mixture was allowed to react at reflux temperature for 26 hours. After the reaction time and cooling, the solid is filtered off and purified by repeated crystallization from ethanol with the addition of activated carbon and silica gel to a constant melting point.

The product obtained had mp. 204-206 ° C, yield 74%. Elemental analysis for C 14 H 13 NO 5 (M275.26) in% -calculated / found:

C 61.15 / 60.69; H, 4.76 / 4.63; N, 5.09 / 4.99.

Infrared spectrum (nujol) v (NH) 3264 cm ^-1 , v (C = O) 1734, 1644 cm ¹ , v (C = C) 1614 cm ¹ , 5 (NH) 1556 cm -1, v (COC) 1274 , 1232 cm ^-1 .

UV spectrum (methanol) λ 234 nm (log 8i 4.35 m ^J mol ¹ ), λ.2 266 nm (log e ₂ 3.97).

Example 2

Following a procedure similar to that of Example 1 from 2-hydroxymethyl-5-methoxy-4H-pyran-4-one (0.033 mol) and 2-octyloxyphenyl isocyanate (0.033 mol), [(5-methoxy-4-oxo-4H) was stirred and -pyran-2-yl) methyl 2-octyloxycarbanilate with m.p. 101-102 ° C in 11% yield.

Elemental analysis for C 22 H 29 NO 3 (M 403.48) calculated%:

C 65.57 / 65.69; H, 7.25 / 7.28; N, 3.48 / 3.12.

Infrared spectrum (nujol) v (NH) 3284 cm ^-1 , v (C = O) 1650 cm ^-1 , v (C = C) 1618 cm ^-1 , δ (NH) 1538 cm ¹ , v (COC) 1260 - 1100 cm ¹ .

UV spectrum (methanol) λι 205 nm (log Ei 4.63 m ¹ , molar ¹ ), λ2 236 nm (log 62 4.25), 276 nm (log 83

4.04).

The compounds prepared are white crystalline substances, soluble in polar solvents and insoluble in non-polar. [(5-Methoxy-4-oxo-4H-pyran-2-yl) methyl] carbanilate and [(5-methoxy-4-oxo-4H-pyran-2yl) methyl] -2-octyloxycarbanilate were tested for fungicidal activity. Biological testing was performed according to general biological methods of I. screening at the Research Institute of Agrochemical Technology in Bratislava. The methodology is given in the literature of Bláhová M .; Krätsmer-Šmogrovic J .; Varkonta Š. Czechness. farm. 31, 264 (1982). A point scale was developed for the evaluation.

antifungal effects in vitro: in vivo:

effective (+) 5 ineffective 1 ineffective (-) 6 effective 3

Results of substance testing:

Hoideum sativum syst. - 2 (in vitro)) carbanal and octyl Erysiphe gramirus syst. 2 oxylurbans

Hordeum sadvunt kont. 3 (in vivo)) carbaniate and octyl Eiysiphe gramirus cont. 3-oxycarbanyl

The results indicated that both [(5-methoxy-4-oxo-4H-pyran-2-yl) methyl] carbanilate and -2-octyloxycarbanilate proved to be effective both in vitro and in vivo when tested for fungicidal activity.

Industrial Applicability [(5-Methoxy-4-oxo-4H-pyran-2-yl) methyl] carbanillates prepared by the process of the invention are particularly useful in cosmetics, in health care for disinfection, in agriculture as fungicides and herbicides.

Claims (2)

PATENT CLAIMS 1. [(5-Methoxy-4-oxo-4H-pyran-2-yl) methyl] carbanilate of the formula I wherein R is H or octyloxy. 2. A process for the preparation of the compound of formula (I) according to claim 1, wherein 1 mol of 2-hydroxymethyl-5-methoxy-4H-pyran-4 is reacted. - an γ-ion in anhydrous xylene with 1 to 2 moles of phenyl isocyanate of the formula (I) wherein R is as defined in claim 1, at the boiling point of the reaction mixture for 5 to 26 hours.